Key publications
Shephard EA, Parkinson MA, Hamilton WT (2019). Recognising laryngeal cancer in primary care: a large case-control study using electronic records.
Br J Gen Pract,
69(679), e127-e133.
Abstract:
Recognising laryngeal cancer in primary care: a large case-control study using electronic records.
BACKGROUND: over 1700 people are diagnosed with laryngeal cancer annually in England. Current National Institute for Health and Care Excellence (NICE) guidelines on referral for suspected laryngeal cancer were based on clinical consensus, in the absence of primary care studies. AIM: to identify and quantify the primary care features of laryngeal cancer. DESIGN AND SETTING: Matched case-control study of patients aged ≥40 years using data from the UK's Clinical Practice Research Datalink. METHOD: Clinical features of laryngeal cancer with which patients had presented to their GP in the year before diagnosis were identified and their association with cancer was assessed using conditional logistic regression. Positive predictive values (PPVs) for each clinical feature were calculated for the consulting population aged >60 years. RESULTS: in total, 806 patients diagnosed with laryngeal cancer between 2000 and 2009 were studied, together with 3559 age-, sex-, and practice-matched controls. Ten features were significantly associated with laryngeal cancer: hoarseness odds ratio [OR] 904 (95% confidence interval [CI] = 277 to 2945); sore throat, first attendance OR 6.2 (95% CI = 3.7 to 10); sore throat, re-attendance OR 7.7 (95% CI = 2.6 to 23); dysphagia OR 6.5 (95% CI = 2.7 to 16); otalgia OR 5.0 (95% CI = 1.9 to 13); dyspnoea, re-attendance OR 4.7 (95% CI = 1.9 to 12); mouth symptoms OR 4.7 (95% CI = 1.8 to 12); recurrent chest infection OR 4.5 (95% CI = 2.4 to 8.5); insomnia OR 2.7 (95% CI = 1.3 to 5.6); and raised inflammatory markers OR 2.5 (95% CI = 1.5 to 4.1). All P-values were 5%. CONCLUSION: These results expand current NICE guidance by identifying new symptom combinations that are associated with laryngeal cancer; they may help GPs to select more appropriate patients for referral.
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Koshiaris C, Van den Bruel A, Oke JL, Nicholson BD, Shephard E, Braddick M, Hamilton W (2018). Early detection of multiple myeloma in primary care using blood tests: a case-control study in primary care.
Br J Gen Pract,
68(674), e586-e593.
Abstract:
Early detection of multiple myeloma in primary care using blood tests: a case-control study in primary care.
BACKGROUND: Multiple myeloma is a haematological cancer characterised by numerous non-specific symptoms leading to diagnostic delay in a large proportion of patients. AIM: to identify which blood tests are useful in suggesting or excluding a diagnosis of myeloma. DESIGN AND SETTING: a matched case-control study set in UK primary care using routinely collected data from the Clinical Practice Research Datalink. METHOD: Symptom prevalence and blood tests were analysed up to 5 years before diagnosis in 2703 cases and 12 157 matched controls. Likelihood ratios (LR) were used to classify tests or their combinations as useful rule-in tests (LR+ = ≥5), or rule-out tests (LR- = ≤0.2). RESULTS: Raised plasma viscosity (PV) had an LR+ = 2.0, 95% confidence interval [CI] = 1.7 to 2.3; erythrocyte sedimentation rate (ESR) 1.9, 95% CI = 1.7 to 2.0; and C-reactive protein (CRP) 1.2, 95% CI = 1.1 to 1.4. A normal haemoglobin had an LR- = 0.42, 95% CI = 0.39 to 0.45; calcium LR- = 0.81, 95% CI = 0.78 to 0.83; and creatinine LR- = 0.80, 95% CI = 0.77 to 0.83. The test combination with the lowest LR- was all normal haemoglobin with calcium and PV, which had an LR- = 0.06, 95% CI = 0.02 to 0.18, though the LR- for normal haemoglobin and PV together was 0.12 (95% CI = 0.07 to 0.23). CONCLUSION: Plasma viscosity and ESR are better for both ruling in and ruling out the disease compared with C-reactive protein. A combination of a normal ESR or PV and normal haemoglobin is a simple rule-out approach for patients currently being tested in primary care.
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Shephard EA, Hamilton WT (2018). Selection of men for investigation of possible testicular cancer in primary care: a large case-control study using electronic patient records.
Br J Gen Pract,
68(673), e559-e565.
Abstract:
Selection of men for investigation of possible testicular cancer in primary care: a large case-control study using electronic patient records.
BACKGROUND: Testicular cancer incidence has risen over the last two decades and is expected to continue to rise. There are no primary care studies on the clinical features of testicular cancer, with recent National Institute for Health and Care Excellence (NICE) guidance based solely upon clinical consensus. AIM: to identify clinical features of testicular cancer and to quantify their risk in primary care patients, with the aim of improving the selection of patients for investigation. DESIGN AND SETTING: a matched case-control study in males aged ≥17 years, using Clinical Practice Research Datalink records. METHOD: Putative clinical features of testicular cancer were identified and analysed using conditional logistic regression. Positive predictive values (PPVs) were calculated for those aged
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Stapley SA, Hamilton WT, Rubin GP, Alsina D, Rutter M, Shephard EA (2017). Clinical features of bowel disease in primary care: a large case-control study. British Journal of General Practice, 67, e336-e344.
Bailey SE, Ukoumunne OC, Shephard EA, Hamilton W (2017). Clinical relevance of thrombocytosis in primary care: a prospective cohort study of cancer incidence using English electronic medical records and cancer registry data.
Br J Gen Pract,
67(659), e405-e413.
Abstract:
Clinical relevance of thrombocytosis in primary care: a prospective cohort study of cancer incidence using English electronic medical records and cancer registry data.
BACKGROUND: Thrombocytosis (raised platelet count) is an emerging risk marker of cancer, but the association has not been fully explored in a primary care context. AIM: to examine the incidence of cancer in a cohort of patients with thrombocytosis, to determine how clinically useful this risk marker could be in predicting an underlying malignancy. DESIGN AND SETTING: a prospective cohort study using Clinical Practice Research Datalink data from 2000 to 2013. METHOD: the 1-year incidence of cancer was compared between two cohorts: 40 000 patients aged ≥40 years with a platelet count of >400 × 109/L (thrombocytosis) and 10 000 matched patients with a normal platelet count. Sub-analyses examined the risk with change in platelet count, sex, age, and different cancer sites. RESULTS: a total of 1098 out of 9435 males with thrombocytosis were diagnosed with cancer (11.6%; 95% confidence interval [CI] = 11.0 to 12.3), compared with 106 of 2599 males without thrombocytosis (4.1%; 95% CI = 3.4 to 4.9). A total of 1355 out of 21 826 females with thrombocytosis developed cancer (6.2%; 95% CI = 5.9 to 6.5), compared with 119 of 5370 females without (2.2%; 95% CI = 1.8 to 2.6). The risk of cancer increased to 18.1% (95% CI = 15.9 to 20.5) for males and 10.1% (95% CI = 9.0 to 11.3) for females, when a second raised platelet count was recorded within 6 months. Lung and colorectal cancer were more commonly diagnosed with thrombocytosis. One-third of patients with thrombocytosis and lung or colorectal cancer had no other symptoms indicative of malignancy. CONCLUSION: Thrombocytosis is a risk marker of cancer in adults; 11.6% and 6.2% cancer incidence in males and females, respectively, is worthy of further investigation for underlying malignancy. These figures well exceed the National Institute for Health and Care Excellence-mandated risk threshold of 3% risk to warrant referral for suspected cancer.
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Shephard EA, Neal RD, Rose P, Walter FM, Litt EJ, Hamilton WT (2015). Quantifying the risk of multiple myeloma from symptoms reported in primary care patients: a large case-control study using electronic records.
Br J Gen Pract,
65(631), e106-e113.
Abstract:
Quantifying the risk of multiple myeloma from symptoms reported in primary care patients: a large case-control study using electronic records.
BACKGROUND: Patients with myeloma experience the longest diagnostic delays compared with patients with other cancers in the UK; 37% are diagnosed through emergency presentations. AIM: to identify and quantify the risk of myeloma from specific clinical features reported by primary care patients. DESIGN AND SETTING: Matched case-control study using General Practice Research Database primary care electronic records. METHOD: Putative clinical features of myeloma were identified and analysed using conditional logistic regression. Positive predictive values (PPVs) were calculated for the consulting population. RESULTS: a total of 2703 patients aged ≥40 years, diagnosed with myeloma between 2000 and 2009, and 12 157 age, sex, and general practice-matched controls were identified. Sixteen features were independently associated with myeloma: hypercalcaemia, odds ratio 11.4 (95% confidence interval [CI] = 7.1 to 18), cytopenia 5.4 (95% CI = 4.6 to 6.4), raised inflammatory markers 4.9 (95% CI = 4.2 to 5.8), fracture 3.1 (95% CI = 2.3 to 4.2), raised mean corpuscular volume 3.1 (95% CI = 2.4 to 4.1), weight loss 3.0 (95% CI = 2.0 to 4.5), nosebleeds 3.0 (95% CI = 1.9 to 4.7), rib pain 2.5 (95% CI = 1.5 to 4.4), back pain 2.2 (95% CI = 2.0 to 2.4), other bone pain 2.1 (95% CI = 1.4 to 3.1), raised creatinine 1.8 (95% CI = 1.5 to 2.2), chest pain 1.6 (95% CI = 1.4 to 1.8), joint pain 1.6 (95% CI = 1.2 to 2.2), nausea 1.5 (95% CI = 1.1 to 2.1), chest infection 1.4 (95% CI = 1.2 to 1.6), and shortness of breath 1.3 (95% CI = 1.1 to 1.5). Individual symptom PPVs were generally 10% for some symptoms when combined with leucopenia or hypercalcaemia. CONCLUSION: Individual symptoms of myeloma in primary care are generally low risk, probably explaining diagnostic delays. Once simple primary care blood tests are taken, risk estimates change. Hypercalcaemia and leucopenia are particularly important abnormalities, and coupled with symptoms, strongly suggest myeloma.
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Publications by year
In Press
Fletcher E, Burns A, Wiering B, Lavu D, Shephard E, Hamilton W, Campbell JL, Abel G (In Press). Workload and Workflow Implications Associated with the Use of Electronic Clinical Decision Support Tools Used By Health Professionals in General Practice: a Scoping Review.
Abstract:
Workload and Workflow Implications Associated with the Use of Electronic Clinical Decision Support Tools Used By Health Professionals in General Practice: a Scoping Review
Abstract
. Background: Electronic clinical decision support tools (eCDS) are increasingly available to assist General Practitioners (GP) with the diagnosis and management of a range of health conditions. It is unclear whether the use of eCDS tools has an impact on GP workload. This scoping review aimed to identify the available evidence on the use of eCDS tools by health professionals in general practice in relation to their impact on workload and workflow.Methods: a scoping review was carried out using the Arksey and O’Malley methodological framework. The search strategy was developed iteratively, with three main aspects: general practice/primary care contexts, risk assessment/decision support tools, and workload-related factors. Three databases were searched in 2019, and updated in 2021, covering articles published since 2009: Medline (Ovid), HMIC (Ovid) and Web of Science (TR). Double screening was completed by two reviewers, and data extracted from included articles were analysed.Results: the search resulted in 5,594 references, leading to 91 full articles after screening. of these, 33 studies were based in the USA, 20 in the UK and 11 in Australia. A further 22 originated from Canada or Europe, with the remaining studies conducted in New Zealand, South Africa and Malaysia. Studies examined the use of eCDS tools and reported some findings related to their impact on workload, including on consultation duration. Most studies were qualitative and exploratory in nature, reporting health professionals’ subjective perceptions of consultation duration as opposed to objectively-measured time spent using tools or consultation durations. Other workload-related findings included impacts on cognitive workload, “workflow” and dialogue with patients, and clinicians’ experience of “alert fatigue”.Conclusions: the published literature on the impact of eCDS tools in general practice showed that limited efforts have focused on investigating the impact of such tools on workload and workflow. To gain an understanding of this area, further research, including quantitative measurement of consultation durations, would be useful to inform the future design and implementation of eCDS tools.
Abstract.
2023
Fletcher E, Burns A, Wiering B, Lavu D, Shephard E, Hamilton W, Campbell JL, Abel G (2023). Workload and workflow implications associated with the use of electronic clinical decision support tools used by health professionals in general practice: a scoping review.
BMC Primary Care,
24(1).
Abstract:
Workload and workflow implications associated with the use of electronic clinical decision support tools used by health professionals in general practice: a scoping review
Abstract
. Background
. Electronic clinical decision support tools (eCDS) are increasingly available to assist General Practitioners (GP) with the diagnosis and management of a range of health conditions. It is unclear whether the use of eCDS tools has an impact on GP workload. This scoping review aimed to identify the available evidence on the use of eCDS tools by health professionals in general practice in relation to their impact on workload and workflow.
.
. Methods
. A scoping review was carried out using the Arksey and O’Malley methodological framework. The search strategy was developed iteratively, with three main aspects: general practice/primary care contexts, risk assessment/decision support tools, and workload-related factors. Three databases were searched in 2019, and updated in 2021, covering articles published since 2009: Medline (Ovid), HMIC (Ovid) and Web of Science (TR). Double screening was completed by two reviewers, and data extracted from included articles were analysed.
.
. Results
. The search resulted in 5,594 references, leading to 95 full articles, referring to 87 studies, after screening. of these, 36 studies were based in the USA, 21 in the UK and 11 in Australia. A further 18 originated from Canada or Europe, with the remaining studies conducted in New Zealand, South Africa and Malaysia. Studies examined the use of eCDS tools and reported some findings related to their impact on workload, including on consultation duration. Most studies were qualitative and exploratory in nature, reporting health professionals’ subjective perceptions of consultation duration as opposed to objectively-measured time spent using tools or consultation durations. Other workload-related findings included impacts on cognitive workload, “workflow” and dialogue with patients, and clinicians’ experience of “alert fatigue”.
.
. Conclusions
. The published literature on the impact of eCDS tools in general practice showed that limited efforts have focused on investigating the impact of such tools on workload and workflow. To gain an understanding of this area, further research, including quantitative measurement of consultation durations, would be useful to inform the future design and implementation of eCDS tools.
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Abstract.
2022
Price SJ, Gibson N, Hamilton WT, Bostock J, Shephard EA (2022). Diagnoses after newly-recorded abdominal pain in primary care: observational cohort study. British Journal of General Practice, 72(721).
Burns A, Donnelly B, Feyi-Waboso J, Shephard E, Calitri R, Tarrant M, Dean SG (2022). How do electronic risk assessment tools affect the communication and understanding of diagnostic uncertainty in the primary care consultation? a systematic review and thematic synthesis.
BMJ Open,
12(6), e060101-e060101.
Abstract:
How do electronic risk assessment tools affect the communication and understanding of diagnostic uncertainty in the primary care consultation? a systematic review and thematic synthesis
ObjectivesTo conduct a systematic review and synthesise qualitative research of electronic risk assessment tools (eRATs) in primary care, examining how they affect the communication and understanding of diagnostic risk and uncertainty. eRATs are computer-based algorithms designed to help clinicians avoid missing important diagnoses, pick up possible symptoms early and facilitate shared decision-making.DesignSystematic search, using predefined criteria of the published literature and synthesis of the qualitative data, using Thematic Synthesis. Database searches on 27 November 2019 were of MEDLINE, Embase, CINAHL and Web of Science, and a secondary search of the references of included articles. Included studies were those involving electronic risk assessment or decision support, pertaining to diagnosis in primary care, where qualitative data were presented. Non-empirical studies and non-English language studies were excluded. 5971 unique studies were identified of which 441 underwent full-text review. 26 studies were included for data extraction. A further two were found from citation searches. Quality appraisal was via the CASP (Critical Appraisal Skills Program) tool. Data extraction was via line by line coding. A thematic synthesis was performed.SettingPrimary care.ResultseRATs included differential diagnosis suggestion tools, tools which produce a future risk of disease development or recurrence or calculate a risk of current undiagnosed disease. Analytical themes were developed to describe separate aspects of the clinical consultation where risk and uncertainty are both central and altered via the use of an eRAT: ‘Novel risk’, ‘Risk refinement’, ‘Autonomy’, ‘Communication’, ‘Fear’ and ‘Mistrust’.ConclusioneRATs may improve the understanding and communication of risk in the primary care consultation. The themes of ‘Fear’ and ‘Mistrust’ could represent potential challenges with eRATs.Trial registration numberCRD219446.
Abstract.
Price SJ, Gibson N, Hamilton WT, King A, Shephard EA (2022). Intra-abdominal cancer risk with abdominal pain: a prospective cohort primary care study.
British Journal of General Practice,
72(718), e361-e368.
Abstract:
Intra-abdominal cancer risk with abdominal pain: a prospective cohort primary care study
BackgroundQuantifying cancer risk in primary care patients with abdominal pain informs diagnostic strategies.AimTo quantify oesophagogastric, colorectal, liver, pancreatic, ovarian, uterine, kidney, and bladder cancer risks associated with newly reported abdominal pain with or without other symptoms, signs, or abnormal blood tests (that is, features) indicative of possible cancer.Design and settingThis was an observational prospective cohort study using Clinical Practice Research Datalink records with English cancer registry linkage.MethodThe authors studied 125 793 patients aged ≥40 years with newly reported abdominal pain in primary care between 1 January 2009 and 31 December 2013. The 1-year cumulative incidence of cancer, and the composite 1-year cumulative incidence of cancers with shared additional features, stratified by age and sex are reported.ResultsWith abdominal pain, overall risk was greater in men and increased with age, reaching 3.4% (95% confidence interval [CI] = 3.0 to 3.7, predominantly colorectal cancer 1.9%, 95% CI = 1.6 to 2.1) in men ≥70 years, compared with their expected incidence of 0.88% (95% CI = 0.87 to 0.89). Additional features increased cancer risk; for example, for men, colorectal or pancreatic cancer risk with abdominal pain plus diarrhoea at 60–69 years of age was 3.1% (95% CI = 1.9 to 4.9) predominantly colorectal cancer (2.2%, 95% CI = 1.2 to 3.8).ConclusionAbdominal pain increases intra-abdominal cancer risk nearly fourfold in men aged ≥70 years, exceeding the 3% threshold warranting investigation. This threshold is surpassed for the >60 years age group only with additional features. These results will help direct appropriate referral and testing strategies for patients based on their demographic profile and reporting features. The authors suggest non-invasive strategies first, such as faecal immunochemical testing, with safety-netting in a shared decision-making framework.
Abstract.
Khan T, El-Sockary Y, Hamilton WT, Shephard EA (2022). Recognizing sinonasal cancer in primary care: a matched case-control study using electronic records.
Fam Pract,
39(3), 354-359.
Abstract:
Recognizing sinonasal cancer in primary care: a matched case-control study using electronic records.
BACKGROUND: Cancers of the nasopharynx, nasal cavity, and accessory sinuses ("sinonasal") are rare in England, with around 750 patients diagnosed annually. There are no specific National Institute for Health and Care Excellence (NICE) referral guidelines for these cancers and no primary care research published. OBJECTIVE: to identify and quantify clinical features of sinonasal cancer in UK primary care patients. METHODS: This matched case-control study used UK Clinical Practice Research Datalink (CPRD) data. Patients were aged ≥40 years with a diagnosis of sinonasal cancer between January 1, 2000 and December 31, 2009 and had consulted their GP in the year before diagnosis. Clinical features of sinonasal cancer were analysed using conditional logistic regression. Positive predictive values (PPVs) for single and combined features were calculated. RESULTS: in total, 155 cases and 697 controls were studied. Nine symptoms and one abnormal investigation were significantly associated with the cancer: nasal mass; odds ratio, 95 (95% confidence interval 7.0, 1315, P = 0.001); head and neck lumps, 68 (12, 387, P < 0.001); epistaxis, 17 (3.9, 70, P < 0.001); rhinorrhoea, 14 (4.6, 44, P < 0.001); visual disturbance, 12 (2.2, 67, P = 0.004); sinusitis, 7.3 (2.2, 25, P = 0.001); sore throat, 6.0 (2.0, 18, P = 0.001); otalgia, 5.4 (1.6, 18, P = 0.007); headache, 3.6 (1.4, 9.5, P = 0.01); raised white cell count, 8.5 (2.8, 27, P < 0.001). Combined PPVs for epistaxis/rhinorrhoea, epistaxis/sinusitis, and rhinorrhoea/sinusitis were 0.62%. CONCLUSION: This is the first primary care study identifying epistaxis, sinusitis, and rhinorrhoea as part of the clinical prodrome of sinonasal cancer. Although no PPVs meet the 3% NICE referral threshold, these results may help clinicians identify who warrants safety-netting and possible specialist referral, potentially reducing the number of advanced-stage diagnoses of sinonasal cancer.
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2021
Quiroga M, Shephard EA, Mounce LTA, Carney M, Hamilton WT, Price SJ (2021). Quantifying the impact of pre-existing conditions on the stage of oesophagogastric cancer at diagnosis: a primary care cohort study using electronic medical records.
Fam Pract,
38(4), 425-431.
Abstract:
Quantifying the impact of pre-existing conditions on the stage of oesophagogastric cancer at diagnosis: a primary care cohort study using electronic medical records.
BACKGROUND: Pre-existing conditions interfere with cancer diagnosis by offering diagnostic alternatives, competing for clinical attention or through patient surveillance. OBJECTIVE: to investigate associations between oesophagogastric cancer stage and pre-existing conditions. METHODS: Retrospective cohort study using Clinical Practice Research Datalink (CPRD) data, with English cancer registry linkage. Participants aged ≥40 years had consulted primary care in the year before their incident diagnosis of oesophagogastric cancer in 01/01/2010-31/12/2015. CPRD records pre-diagnosis were searched for codes denoting clinical features of oesophagogastric cancer and for pre-existing conditions, including those providing plausible diagnostic alternatives for those features. Logistic regression analysed associations between stage and multimorbidity (≥2 conditions; reference category: no multimorbidity) and having 'diagnostic alternative(s)', controlling for age, sex, deprivation and cancer site. RESULTS: of 2444 participants provided, 695 (28%) were excluded for missing stage, leaving 1749 for analysis (1265/1749, 72.3% had advanced-stage disease). Multimorbidity was associated with stage [odds ratio 0.63, 95% confidence interval (CI) 0.47-0.85, P = 0.002], with moderate evidence of an interaction term with sex (1.76, 1.08-2.86, P = 0.024). There was no association between alternative explanations and stage (odds ratio 1.18, 95% CI 0.87-1.60, P = 0.278). CONCLUSIONS: in men, multimorbidity is associated with a reduced chance of advanced-stage oesophagogastric cancer, to levels seen collectively for women.
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2020
Carney MH, Price S, Shephard E, Mounce L, Quiroga M, Hamilton W (2020). Abstract A25: Effect of pre-existing conditions on bladder cancer diagnosis: a cohort study using electronic primary care records.
Carney M, Quiroga M, Mounce L, Shephard E, Hamilton W, Price S (2020). Effect of pre-existing conditions on bladder cancer stage at diagnosis: a cohort study using electronic primary care records in the UK.
British Journal of General Practice,
70(698), E629-E635.
Abstract:
Effect of pre-existing conditions on bladder cancer stage at diagnosis: a cohort study using electronic primary care records in the UK
Background Pre-existing concurrent medical conditions (multimorbidity) complicate cancer diagnosis when they provide plausible diagnostic alternatives for cancer symptoms. Aim to investigate associations in bladder cancer between: first, pre-existing condition count and advanced-stage diagnosis; and, second, comorbidities that share symptoms with bladder cancer and advanced-stage diagnosis. Design and setting This observational UK cohort study was set in the Clinical Practice Research Datalink with Public Health England National Cancer Registration and Analysis Service linkage. Method Included participants were aged ≥40 years with an incident diagnosis of bladder cancer between 1 January 2000 and 31 December 2015, and primary care records of attendance for haematuria, dysuria, or abdominal mass in the year before diagnosis. Stage at diagnosis (stage 1 or 2 versus stage 3 or 4) was the outcome variable. Putative explanatory variables using logistic regression were examined, including patient-level count of pre-existing conditions and ‘alternative-explanations’, indicating whether pre-existing condition(s) were plausible diagnostic alternatives for the index cancer symptom. Results in total, 1468 patients (76.4% male) were studied, of which 399 (35.6%) males and 217 (62.5%) females had alternative explanations for their index cancer symptom, the most common being urinary tract infection with haematuria. Females were more likely than males to be diagnosed with advanced-stage cancer (adjusted odds ratio [aOR] 1.62; 95% confidence interval [CI] = 1.20 to 2.18; P = 0.001). Alternative explanations were strongly associated with advanced-stage diagnosis in both sexes (aOR 1.69; 95% CI = 1.20 to 2.39; P = 0.003). Conclusion Alternative explanations were associated with advanced-stage diagnosis of bladder cancer. Females were more likely than males to be diagnosed with advanced-stage disease, but the effect was not driven entirely by alternative explanations.
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Hopkins R, Bailey SER, Hamilton WT, Shephard EA (2020). Microcytosis as a risk marker of cancer in primary care: a cohort study using electronic patient records.
British Journal of General Practice,
70(696), E457-E462.
Abstract:
Microcytosis as a risk marker of cancer in primary care: a cohort study using electronic patient records
Background Microcytosis (smaller than normal red blood cells) has previously been identified as a possible early risk marker for some cancers. However, the role of microcytosis across all cancers has not been fully investigated. Aim to examine cancer incidence in a cohort of patients with microcytosis, with and without accompanying anaemia. Design and setting Cohort study of patients aged ≥40 years using UK primary care electronic patient records. Method the 1-year cancer incidence was compared between cohorts of patients with a mean red cell volume of
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2019
Calitri R, Mounce L, Abel G, Campbell J, Spencer A, Medina-Lara A, Pitt M, Shepard E, Warren F, Dean S, et al (2019). Protocol for a pragmatic cluster randomised controlled trial assessing the clinical effectiveness and cost effectiveness of electronic risk-assessment tools for cancer for patients in general practice (ERICA).
Author URL.
Shephard EA, Parkinson MA, Hamilton WT (2019). Recognising laryngeal cancer in primary care: a large case-control study using electronic records.
Br J Gen Pract,
69(679), e127-e133.
Abstract:
Recognising laryngeal cancer in primary care: a large case-control study using electronic records.
BACKGROUND: over 1700 people are diagnosed with laryngeal cancer annually in England. Current National Institute for Health and Care Excellence (NICE) guidelines on referral for suspected laryngeal cancer were based on clinical consensus, in the absence of primary care studies. AIM: to identify and quantify the primary care features of laryngeal cancer. DESIGN AND SETTING: Matched case-control study of patients aged ≥40 years using data from the UK's Clinical Practice Research Datalink. METHOD: Clinical features of laryngeal cancer with which patients had presented to their GP in the year before diagnosis were identified and their association with cancer was assessed using conditional logistic regression. Positive predictive values (PPVs) for each clinical feature were calculated for the consulting population aged >60 years. RESULTS: in total, 806 patients diagnosed with laryngeal cancer between 2000 and 2009 were studied, together with 3559 age-, sex-, and practice-matched controls. Ten features were significantly associated with laryngeal cancer: hoarseness odds ratio [OR] 904 (95% confidence interval [CI] = 277 to 2945); sore throat, first attendance OR 6.2 (95% CI = 3.7 to 10); sore throat, re-attendance OR 7.7 (95% CI = 2.6 to 23); dysphagia OR 6.5 (95% CI = 2.7 to 16); otalgia OR 5.0 (95% CI = 1.9 to 13); dyspnoea, re-attendance OR 4.7 (95% CI = 1.9 to 12); mouth symptoms OR 4.7 (95% CI = 1.8 to 12); recurrent chest infection OR 4.5 (95% CI = 2.4 to 8.5); insomnia OR 2.7 (95% CI = 1.3 to 5.6); and raised inflammatory markers OR 2.5 (95% CI = 1.5 to 4.1). All P-values were 5%. CONCLUSION: These results expand current NICE guidance by identifying new symptom combinations that are associated with laryngeal cancer; they may help GPs to select more appropriate patients for referral.
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2018
Shephard EA, Hamilton WT (2018). Corrections: Selection of men for investigation of possible testicular cancer in primary care: a large case-control study using electronic patient records (British Journal of General Practice(2018) DOI: 10.3399/bjgp18X697949).
British Journal of General Practice,
68(674).
Abstract:
Corrections: Selection of men for investigation of possible testicular cancer in primary care: a large case-control study using electronic patient records (British Journal of General Practice(2018) DOI: 10.3399/bjgp18X697949)
Research by Shephard EA and Hamilton WT, Selection of men for investigation of possible testicular cancer in primary care: a large case-control study using electronic patient records. Br J Gen Pract 2018; DOI: Https://doi.org/10.3399/ bjgp18X697949 showed an inaccuracy in the print version. The printed version states 'Testicular swelling alone has a PPV for cancer just below the 3% threshold, but when combined with testicular, groin or abdominal pain, particularly in men aged >50 years, the likelihood of cancer is considerably greater.' the corrected version should read 'A testicular lump alone has a PPV for cancer just below the 3% threshold, but when combined with testicular swelling, pain or abdominal pain in men
Abstract.
Koshiaris C, Van den Bruel A, Oke JL, Nicholson BD, Shephard E, Braddick M, Hamilton W (2018). Early detection of multiple myeloma in primary care using blood tests: a case-control study in primary care.
Br J Gen Pract,
68(674), e586-e593.
Abstract:
Early detection of multiple myeloma in primary care using blood tests: a case-control study in primary care.
BACKGROUND: Multiple myeloma is a haematological cancer characterised by numerous non-specific symptoms leading to diagnostic delay in a large proportion of patients. AIM: to identify which blood tests are useful in suggesting or excluding a diagnosis of myeloma. DESIGN AND SETTING: a matched case-control study set in UK primary care using routinely collected data from the Clinical Practice Research Datalink. METHOD: Symptom prevalence and blood tests were analysed up to 5 years before diagnosis in 2703 cases and 12 157 matched controls. Likelihood ratios (LR) were used to classify tests or their combinations as useful rule-in tests (LR+ = ≥5), or rule-out tests (LR- = ≤0.2). RESULTS: Raised plasma viscosity (PV) had an LR+ = 2.0, 95% confidence interval [CI] = 1.7 to 2.3; erythrocyte sedimentation rate (ESR) 1.9, 95% CI = 1.7 to 2.0; and C-reactive protein (CRP) 1.2, 95% CI = 1.1 to 1.4. A normal haemoglobin had an LR- = 0.42, 95% CI = 0.39 to 0.45; calcium LR- = 0.81, 95% CI = 0.78 to 0.83; and creatinine LR- = 0.80, 95% CI = 0.77 to 0.83. The test combination with the lowest LR- was all normal haemoglobin with calcium and PV, which had an LR- = 0.06, 95% CI = 0.02 to 0.18, though the LR- for normal haemoglobin and PV together was 0.12 (95% CI = 0.07 to 0.23). CONCLUSION: Plasma viscosity and ESR are better for both ruling in and ruling out the disease compared with C-reactive protein. A combination of a normal ESR or PV and normal haemoglobin is a simple rule-out approach for patients currently being tested in primary care.
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Author URL.
Shephard EA, Hamilton WT (2018). Selection of men for investigation of possible testicular cancer in primary care: a large case-control study using electronic patient records.
Br J Gen Pract,
68(673), e559-e565.
Abstract:
Selection of men for investigation of possible testicular cancer in primary care: a large case-control study using electronic patient records.
BACKGROUND: Testicular cancer incidence has risen over the last two decades and is expected to continue to rise. There are no primary care studies on the clinical features of testicular cancer, with recent National Institute for Health and Care Excellence (NICE) guidance based solely upon clinical consensus. AIM: to identify clinical features of testicular cancer and to quantify their risk in primary care patients, with the aim of improving the selection of patients for investigation. DESIGN AND SETTING: a matched case-control study in males aged ≥17 years, using Clinical Practice Research Datalink records. METHOD: Putative clinical features of testicular cancer were identified and analysed using conditional logistic regression. Positive predictive values (PPVs) were calculated for those aged
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2017
Stapley SA, Hamilton WT, Rubin GP, Alsina D, Rutter M, Shephard EA (2017). Clinical features of bowel disease in primary care: a large case-control study. British Journal of General Practice, 67, e336-e344.
Bailey SE, Ukoumunne OC, Shephard EA, Hamilton W (2017). Clinical relevance of thrombocytosis in primary care: a prospective cohort study of cancer incidence using English electronic medical records and cancer registry data.
Br J Gen Pract,
67(659), e405-e413.
Abstract:
Clinical relevance of thrombocytosis in primary care: a prospective cohort study of cancer incidence using English electronic medical records and cancer registry data.
BACKGROUND: Thrombocytosis (raised platelet count) is an emerging risk marker of cancer, but the association has not been fully explored in a primary care context. AIM: to examine the incidence of cancer in a cohort of patients with thrombocytosis, to determine how clinically useful this risk marker could be in predicting an underlying malignancy. DESIGN AND SETTING: a prospective cohort study using Clinical Practice Research Datalink data from 2000 to 2013. METHOD: the 1-year incidence of cancer was compared between two cohorts: 40 000 patients aged ≥40 years with a platelet count of >400 × 109/L (thrombocytosis) and 10 000 matched patients with a normal platelet count. Sub-analyses examined the risk with change in platelet count, sex, age, and different cancer sites. RESULTS: a total of 1098 out of 9435 males with thrombocytosis were diagnosed with cancer (11.6%; 95% confidence interval [CI] = 11.0 to 12.3), compared with 106 of 2599 males without thrombocytosis (4.1%; 95% CI = 3.4 to 4.9). A total of 1355 out of 21 826 females with thrombocytosis developed cancer (6.2%; 95% CI = 5.9 to 6.5), compared with 119 of 5370 females without (2.2%; 95% CI = 1.8 to 2.6). The risk of cancer increased to 18.1% (95% CI = 15.9 to 20.5) for males and 10.1% (95% CI = 9.0 to 11.3) for females, when a second raised platelet count was recorded within 6 months. Lung and colorectal cancer were more commonly diagnosed with thrombocytosis. One-third of patients with thrombocytosis and lung or colorectal cancer had no other symptoms indicative of malignancy. CONCLUSION: Thrombocytosis is a risk marker of cancer in adults; 11.6% and 6.2% cancer incidence in males and females, respectively, is worthy of further investigation for underlying malignancy. These figures well exceed the National Institute for Health and Care Excellence-mandated risk threshold of 3% risk to warrant referral for suspected cancer.
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2016
Price SJ, Stapley SA, Shephard E, Barraclough K, Hamilton WT (2016). Is omission of free text records a possible source of data loss and bias in Clinical Practice Research Datalink studies? a case-control study.
BMJ Open,
6(5).
Abstract:
Is omission of free text records a possible source of data loss and bias in Clinical Practice Research Datalink studies? a case-control study
Objectives: to estimate data loss and bias in studies of Clinical Practice Research Datalink (CPRD) data that restrict analyses to Read codes, omitting anything recorded as text. Design: Matched case-control study. Setting: Patients contributing data to the CPRD. Participants: 4915 bladder and 3635 pancreatic, cancer cases diagnosed between 1 January 2000 and 31 December 2009, matched on age, sex and general practitioner practice to up to 5 controls (bladder: n=21 718; pancreas: n=16 459). The analysis period was the year before cancer diagnosis. Primary and secondary outcome measures: Frequency of haematuria, jaundice and abdominal pain, grouped by recording style: Read code or text-only (ie, hidden text). The association between recording style and case-control status (χ2test). For each feature, the odds ratio (OR; conditional logistic regression) and positive predictive value (PPV; Bayes' theorem) for cancer, before and after addition of hidden text records. Results: of the 20 958 total records of the features, 7951 (38%) were recorded in hidden text. Hidden text recording was more strongly associated with controls than with cases for haematuria (140/336=42% vs 556/3147=18%) in bladder cancer (χ2test, p
Abstract.
Shephard EA, Neal RD, Rose PW, Walter FM, Hamilton W (2016). Symptoms of adult chronic and acute leukaemia before diagnosis: large primary care case-control studies using electronic records.
Br J Gen Pract,
66(644), e182-e188.
Abstract:
Symptoms of adult chronic and acute leukaemia before diagnosis: large primary care case-control studies using electronic records.
BACKGROUND: Leukaemia is the eleventh commonest UK cancer. The four main subtypes have different clinical profiles, particularly between chronic and acute types. AIM: to identify the symptom profiles of chronic and acute leukaemia in adults in primary care. DESIGN AND SETTING: Matched case-control studies using Clinical Practice Research Datalink records. METHOD: Putative symptoms of leukaemia were identified in the year before diagnosis. Conditional logistic regression was used for analysis, and positive predictive values (PPVs) were calculated to estimate risk. RESULTS: of cases diagnosed between 2000 and 2009, 4655 were aged ≥40 years (2877 chronic leukaemia (CL), 937 acute leukaemia (AL), 841 unreported subtype). Ten symptoms were independently associated with CL, the three strongest being: lymphadenopathy (odds ratio [OR] 22, 95% confidence interval [CI] = 13 to 36), weight loss (OR 3.0, 95% CI = 2.1 to 4.2), and bruising (OR 2.3, 95% CI = 1.6 to 3.2). Thirteen symptoms were independently associated with AL, the three strongest being: nosebleeds and/or bleeding gums (OR 5.7, 95% CI = 3.1 to 10), fever (OR 5.3, 95% CI = 2.7 to 10), and fatigue (OR 4.4, 95% CI = 3.3 to 6.0). No individual symptom or combination of symptoms had a PPV >1%. CONCLUSION: the symptom profiles of CL and AL have both overlapping and distinct features. This presents a dichotomy for GPs: diagnosis, by performing a full blood count, is easy; however, the symptoms of leukaemia are non-specific and of relatively low risk. This explains why many leukaemia diagnoses are unexpected findings.
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2015
Price SJ, Shephard EA, Stapley SA, Barraclough K, Hamilton WT (2015). Does the GP method of recording possible cancer symptoms reflect the probability that cancer is present?.
EUROPEAN JOURNAL OF CANCER CARE,
24, 30-30.
Author URL.
Shephard EA, Neal RD, Rose PW, Walter FM, Hamilton WT (2015). Quantifying the risk of Hodgkin lymphoma in symptomatic primary care patients aged ≥40 years: a case-control study using electronic records.
Br J Gen Pract,
65(634), e289-e294.
Abstract:
Quantifying the risk of Hodgkin lymphoma in symptomatic primary care patients aged ≥40 years: a case-control study using electronic records.
BACKGROUND: in the UK, approximately five people are diagnosed with Hodgkin lymphoma (HL) daily. One-tenth of diagnoses are in those aged >75 years. AIM: to establish a symptom profile of HL and quantify their risk in primary care patients aged ≥40 years. DESIGN AND SETTING: Matched case-control study using Clinical Practice Research Datalink patient records. METHOD: Putative clinical features of HL were identified in the year before diagnosis. Results were analysed using conditional logistic regression and positive predictive values (PPVs) calculated for the consulting population. RESULTS: Two-hundred and eighty-three patients aged ≥40 years, diagnosed with HL between 2000 and 2009, and 1237 age, sex, and general practice-matched participants were studied. Six features were independently associated with HL: lymphadenopathy (OR 280, 95% confidence interval [CI] = 25 to 3100), head and neck mass not described as lymphadenopathy (OR 260, 95% CI = 21 to 3200), other mass (OR 12, 95% CI = 4.4 to 35), thrombocytosis (OR 6.0, 95% CI = 2.6 to 14), raised inflammatory markers (OR 5.2, 95% CI = 3.0 to 9.0), and low full blood count (OR 2.8, 95% CI = 1.6 to 4.8). Lymphadenopathy per se has a positive predictive value (PPV) of 5.6% for HL in patients aged ≥60 years. CONCLUSION: Consistent with secondary care findings, lymphadenopathy is the clinical feature with the highest risk of HL in primary care and warrants urgent investigation.
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Shephard EA, Neal RD, Rose P, Walter FM, Litt EJ, Hamilton WT (2015). Quantifying the risk of multiple myeloma from symptoms reported in primary care patients: a large case-control study using electronic records.
Br J Gen Pract,
65(631), e106-e113.
Abstract:
Quantifying the risk of multiple myeloma from symptoms reported in primary care patients: a large case-control study using electronic records.
BACKGROUND: Patients with myeloma experience the longest diagnostic delays compared with patients with other cancers in the UK; 37% are diagnosed through emergency presentations. AIM: to identify and quantify the risk of myeloma from specific clinical features reported by primary care patients. DESIGN AND SETTING: Matched case-control study using General Practice Research Database primary care electronic records. METHOD: Putative clinical features of myeloma were identified and analysed using conditional logistic regression. Positive predictive values (PPVs) were calculated for the consulting population. RESULTS: a total of 2703 patients aged ≥40 years, diagnosed with myeloma between 2000 and 2009, and 12 157 age, sex, and general practice-matched controls were identified. Sixteen features were independently associated with myeloma: hypercalcaemia, odds ratio 11.4 (95% confidence interval [CI] = 7.1 to 18), cytopenia 5.4 (95% CI = 4.6 to 6.4), raised inflammatory markers 4.9 (95% CI = 4.2 to 5.8), fracture 3.1 (95% CI = 2.3 to 4.2), raised mean corpuscular volume 3.1 (95% CI = 2.4 to 4.1), weight loss 3.0 (95% CI = 2.0 to 4.5), nosebleeds 3.0 (95% CI = 1.9 to 4.7), rib pain 2.5 (95% CI = 1.5 to 4.4), back pain 2.2 (95% CI = 2.0 to 2.4), other bone pain 2.1 (95% CI = 1.4 to 3.1), raised creatinine 1.8 (95% CI = 1.5 to 2.2), chest pain 1.6 (95% CI = 1.4 to 1.8), joint pain 1.6 (95% CI = 1.2 to 2.2), nausea 1.5 (95% CI = 1.1 to 2.1), chest infection 1.4 (95% CI = 1.2 to 1.6), and shortness of breath 1.3 (95% CI = 1.1 to 1.5). Individual symptom PPVs were generally 10% for some symptoms when combined with leucopenia or hypercalcaemia. CONCLUSION: Individual symptoms of myeloma in primary care are generally low risk, probably explaining diagnostic delays. Once simple primary care blood tests are taken, risk estimates change. Hypercalcaemia and leucopenia are particularly important abnormalities, and coupled with symptoms, strongly suggest myeloma.
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Shephard EA, Neal RD, Rose PW, Walter FM, Hamilton WT (2015). Quantifying the risk of non-Hodgkin lymphoma in symptomatic primary care patients aged ≥40 years: a large case-control study using electronic records.
Br J Gen Pract,
65(634), e281-e288.
Abstract:
Quantifying the risk of non-Hodgkin lymphoma in symptomatic primary care patients aged ≥40 years: a large case-control study using electronic records.
BACKGROUND: Non-Hodgkin lymphoma (NHL) is the sixth most common cancer in the UK; approximately 35 people are diagnosed and 13 die from the disease daily. AIM: to identify the primary care clinical features of NHL and quantify their risk in symptomatic patients. DESIGN AND SETTING: Matched case-control study using Clinical Practice Research Datalink patient records. METHOD: Putative clinical features of NHL were identified in the year before diagnosis. Results were analysed using conditional logistic regression and positive predictive values (PPVs). RESULTS: a total of 4362 patients aged ≥40 years, diagnosed with NHL between 2000 and 2009, and 19 468 age, sex, and general practice-matched controls were studied. Twenty features were independently associated with NHL. The five highest risk symptoms were lymphadenopathy, odds ratio (OR) 263 (95% CI = 133 to 519), head and neck mass not described as lymphadenopathy OR 49 (95% CI = 32 to 74), other mass OR 12 (95% CI = 10 to 16), weight loss OR 3.2 (95% CI = 2.3 to 4.4), and abdominal pain OR 2.5 (95% CI = 2.1 to 2.9). Lymphadenopathy has a PPV of 13% for NHL in patients ≥60 years. Weight loss in conjunction with repeated back pain or raised gamma globulin had PPVs >2%. CONCLUSION: Unexplained lymphadenopathy in patients aged ≥60 years produces a very high risk of NHL in primary care. These patients warrant urgent investigation, potentially sooner than 6 weeks from initial presentation where the GP is particularly concerned.
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2014
Shephard EA (2014). Erratum: Clinical features of bladder cancer in primary care (British Journal of General Practice (2012) DOI: 10.3399/bjgp12X654560). British Journal of General Practice, 64(620).
Bailey SER, Ukoumunne OC, Shephard EA, Hamilton W (2014). How useful is thrombocytosis in predicting an underlying cancer in primary care?: systematic review protocol.
Price SJ, Shephard EA, Stapley SA, Barraclough K, Hamilton WT (2014). Non-visible versus visible haematuria and bladder cancer risk: a study of electronic records in primary care.
Br J Gen Pract,
64(626), e584-e589.
Abstract:
Non-visible versus visible haematuria and bladder cancer risk: a study of electronic records in primary care.
BACKGROUND: Diagnosis of bladder cancer relies on investigation of symptoms presented to primary care, notably visible haematuria. The importance of non-visible haematuria has never been estimated. AIM: to estimate the risk of bladder cancer with non-visible haematuria. DESIGN AND SETTING: a case-control study using UK electronic primary care medical records, including uncoded data to supplement coded records. METHOD: a total of 4915 patients (aged ≥40 years) diagnosed with bladder cancer between January 2000 and December 2009 were selected from the Clinical Practice Research Datalink and matched to 21 718 controls for age, sex, and practice. Variables for visible and non-visible haematuria were derived from coded and uncoded data. Analyses used multivariable conditional logistic regression, followed by estimation of positive predictive values (PPVs) for bladder cancer using Bayes' theorem. RESULTS: Non-visible haematuria (coded/uncoded data) was independently associated with bladder cancer: odds ratio (OR) 20 (95% confidence interval [CI] =12 to 33). The PPV of non-visible haematuria was 1.6% (95% CI = 1.2 to 2.1) in those aged ≥60 years and 0.8% (95% CI = 0.1 to 5.6) in 40-59-year-olds. The PPV of visible haematuria was 2.8% (95% CI = 2.5 to 3.1) and 1.2% (95% CI = 0.6 to 2.3) for the same age groups respectively, lower than those calculated using coded data alone. The proportion of records of visible haematuria in coded, rather than uncoded, format was higher in cases than in controls (P
Abstract.
Author URL.
Bailey SER (2014). PROTOCOL: How useful is thrombocytosis in predicting underlying cancer? a systematic review.
Price SJ, Shephard EA, Stapley SA, Barraclough K, Hamilton WT (2014). The risk of bladder cancer with non-visible haematuria: a primary care study using electronic records.
EUROPEAN JOURNAL OF CANCER CARE,
23, 32-32.
Author URL.
2013
Shephard E, Neal R, Rose P, Walter F, Hamilton WT (2013). Clinical features of kidney cancer in primary care: a case-control study using primary care records.
Br J Gen Pract,
63(609), e250-e255.
Abstract:
Clinical features of kidney cancer in primary care: a case-control study using primary care records.
BACKGROUND: Kidney cancer accounts for over 4000 UK deaths annually, and is one of the cancer sites with a poor mortality record compared with Europe. AIM: to identify and quantify all clinical features of kidney cancer in primary care. DESIGN: Case-control study, using General Practice Research Database records. METHOD: a total of 3149 patients aged ≥40 years, diagnosed with kidney cancer between 2000 and 2009, and 14 091 age, sex and practice-matched controls, were selected. Clinical features associated with kidney cancer were identified, and analysed using conditional logistic regression. Positive predictive values for features of kidney cancer were estimated. RESULTS: Cases consulted more frequently than controls in the year before diagnosis: median 16 consultations (interquartile range 10-25) versus 8 (4-15): P
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2012
Shephard EA, Stapley S, Neal RD, Rose P, Walter FM, Hamilton WT (2012). Clinical features of bladder cancer in primary care.
Br J Gen Pract,
62(602), e598-e604.
Abstract:
Clinical features of bladder cancer in primary care.
BACKGROUND: Bladder cancer accounts for over 150,000 deaths worldwide. No screening is available, so diagnosis depends on investigations of symptoms. of these, only visible haematuria has been studied in primary care. AIM: to identify and quantify the features of bladder cancer in primary care. DESIGN AND SETTING: Case-control study, using electronic medical records from UK primary care. METHOD: Participants were 4915 patients aged ≥40 years, diagnosed with bladder cancer January 2000 to December 2009, and 21,718 age, sex, and practice-matched controls, were selected from the General Practice Research Database, UK. All clinical features independently associated with bladder cancer using conditional logistic regression were identified, and their positive predictive values for bladder cancer, singly and in combination, were estimated. RESULTS: Cases consulted their GP more frequently than controls before diagnosis: median 15 consultations (interquartile range 9-22) versus 8 (4-15): P
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Temple CM, Shephard EE (2012). Exceptional lexical skills but executive language deficits in school starters and young adults with Turners syndrome: Implications for X chromosome effects on brain function. Brain and Language, 120(3), 345-359.
2011
Shephard E, Stapley S, Hamilton W (2011). The use of electronic databases in primary care research. Family Practice, 28(4), 352-354.
