Back to CPRD @ Cambridge Code Lists Index
These are our Version 1.1 Lists, as at 1st October 2018, for the CPRD GOLD medcodes.
The first table consists of :
- 46 code lists = 35 MEDCODE lists + 11 PRODCODE lists, which help to describe 37 ‘conditions’ (or 38 if separating anxiety / depression), including all those described in the paper by Payne et al (paper submitted)
- Some conditions use a single MEDCODE list, some a single PRODCODE list – and some a combination of the two.
- PAINFUL CONDITION involves a primary inclusion and a secondary exclusion list of PRODCODES.
The second table consists of the additional lists, or subsets, or combinations of lists in the first table, that permit the calculation of a CHARLSON comorbidity index, using consistent Long Term Condition (LTC) definitions where these overlap. Khan et al (1) have also published definitions for a Charlson score.
Each zipped file from the Download link contains :
- One Description CSV, with a summary description, provenance & citations & links & code count of the created list.
- One Detail CSV with each code & corresponding description per row (including readcodes for medcodes and drug description for product codes)
Current Code Lists on 38 Common Conditions
| List ID / Download Link | CONDITION | Description | Provenance | Prevalence % | Usage in Searchable Dataset |
|---|---|---|---|---|---|
| ALC138 (MEDCODES) | Alcohol problems | Read code list indicating any form of chronic alcohol problem | List developed by Cambridge CPRD group, based on Scottish Information Services Division (ISD) terminology | 0.018 | Read code ever recorded |
| ANO139 (MEDCODES) | Anorexia or bulimia | Read code list indicating chronic anorexia or bulimia | List developed by Cambridge CPRD group. | 0.005 | Read code ever recorded |
| ANX140 (MEDCODES) | Anxiety & other neurotic, stress related & somatoform disorders | (Also see depression) - We suggest that this condition be defined using both recent Read codes OR use of relevant medications. The drugs overlap with drugs used to treat depression, and a mixture of anxiety and depression is common. Therefore our group's consensus is to use a combination of anxiety and/or depression as one disease/illness grouping, both defined by read code or drugs. | List developed by Cambridge CPRD group, based on Scottish Information Services Division (ISD) terminology | 0.17 | Read code in last 12 months (MEDCODES) OR 4 or more anxiolytic/hypnotic prescriptions in last 12 months (PRODCODES) |
| ANX141 (PRODCODES) | Anxiety & other neurotic, stress related & somatoform disorders | (Also see depression) - We suggest that this condition be defined using both recent Read codes OR use of relevant medications. The drugs overlap with drugs used to treat depression, and a mixture of anxiety and depression is common. Therefore our group's consensus is to use a combination of anxiety and/or depression as one disease/illness grouping, both defined by read code or drugs. | List developed by Cambridge CPRD group, created using Chapter 4.1.1 (Hypnotics and Anxiolytics) in the BNF, but it excluded melatonin, promethazine, oxybate, chloral hydrate, chlorodiazepoxide. It also included the anxiolytics in chapter 4.1.2 and trazad | Read code in last 12 months (MEDCODES) OR 4 or more anxiolytic/hypnotic prescriptions in last 12 months (PRODCODES) | |
| AST142 (MEDCODES) | Asthma (currently treated) | Run asthma Read code list with prescription list in the last 12 months . Asthma drugs will need updating as new drugs come out to include post-2012 new drugs. | List developed by Cambridge CPRD group, sourced from QOF and 10.1136/bmj.g330 (1) | 0.042 | Read code ever recorded (MEDCODES) AND Any prescription in the last 12 months (PRODCODES) |
| AST127 (PRODCODES) | Asthma (currently treated) | Run asthma Read code list with prescription list in the last 12 months . Asthma drugs will need updating as new drugs come out to include post-2012 new drugs. | List developed by Cambridge CPRD group, from code browser with BNF chapters 3.1, 3.2, and 3.3.1 and 3.3.2 (but not 3.3.3 as these are COPD meds only). Within 3.1, nebuliser diluents (i.e. saline solutions not containing medicines), drug delivery devices & peak flow meters were excluded. | Read code ever recorded (MEDCODES) AND Any prescription in the last 12 months (PRODCODES) | |
| ATR143 (MEDCODES) | Atrial fibrillation | This is the same as the QOF 2012 list, checked by Cambridge | 0.03 | Read code ever recorded | |
| BLI144 (MEDCODES) | Blindness and low vision | List developed by Cambridge CPRD group, based on Scottish ISD list. NB - It was decided to omit "O/E.." terms as these may describe temporary acute symptoms. Poor vision/blindness registration codes and "F4.." codes describing longstanding visual problem | 0.01 | Read code ever recorded | |
| BRO145 (MEDCODES) | Bronchiectasis | Read codes indicating bronchiectasis | ISD list, confirmed using CPRD product browser tool. | 0.004 | Read code ever recorded |
| CAN146 (MEDCODES) | Cancer - [New] Diagnosis in last five years | A Read code list of cancer diagnoses | List developed by Cambridge CPRD group. | 0.012 | Read code [first] recorded in last 5 years |
| CKD147 (MEDCODES) | Chronic kidney disease | ReadCodes to capture blood tests - When the best (highest value) of the last 2 eGFR readings is < 60 mL/min; eGFR tests are recorded as enttype 466 | List developed by Cambridge CPRD group, simpified from McDonald et al, Kidney International 2016 https://doi.org/10.1016/j.kint.2016.04.010 (3) | 0.035 | The best (highest value) of the last 2 eGFR readings is < 60 mL/min |
| CLD148 (MEDCODES) | Chronic Liver Disease and Viral Hepatitis | We have combined chronic liver disease with viral hepatitis as there was risk of substantial overlap if both were used. Transient (e.g. hep A) hepatitis codes we have attempted to exclude. | List developed by Cambridge CPRD group, based on original lists from Clinicalcodes.org. | 0.006 | Read code ever recorded |
| SIN149 (MEDCODES) | Chronic sinusitis | List developed by Cambridge CPRD group. | 0.029 | Read code ever recorded | |
| CON150 (PRODCODES) | Constipation (Treated) | Product list for laxatives | List developed by Cambridge CPRD group, using CPRD’s product code browser and BNF to identify laxatives. | 0.022 | 4 or more laxative prescriptions in last year |
| COP151 (MEDCODES) | COPD | List developed by Cambridge CPRD group, based on the QOF2012 list. Likely to be sensitive as broad range of codes. | 0.031 | Read code ever recorded | |
| CHD126 (MEDCODES) | Coronary heart disease | List developed by Cambridge CPRD group. An attempt at a comprehensive Read code list covering angina, myocardial infarction and IHD procedures to sensitively capture all IHD. We used the codelists developed for the following article: Hawkins NM, Scholes S, Bajekal M et al (2) | 0.055 | Read code ever recorded | |
| DEM131 (MEDCODES) | Dementia | List developed by Cambridge CPRD group, based on two published dementia diagnosis lists (Grant e al, 2013; Khan et al 2010) plus a hand search using the CPRD medical diagnosis browser. | 0.013 | Read code ever recorded | |
| DEP152 (MEDCODES) | Depression | List developed by Cambridge CPRD group. | 0.103 | Read code recorded in last 12 months (MEDCODES) OR 4 or more anti-depressant prescriptions (excluding low dose tricyclics) in last 12 months (PRODCODES) | |
| DEP153 (PRODCODES) | Depression | List developed by Cambridge CPRD group. | Read code recorded in last 12 months (MEDCODES) OR 4 or more anti-depressant prescriptions (excluding low dose tricyclics) in last 12 months (PRODCODES) | ||
| DIB128 (MEDCODES) | Diabetes | List developed by Cambridge CPRD group, based on this paper : 10.1371/journal.pone.0179392 (4) . Created and selected after comparison with other published lists. | 0.059 | Read code ever recorded | |
| DIV154 (MEDCODES) | Diverticular disease of intestine | List developed by Cambridge CPRD group, based on Scottish Information Services Division (ISD) terminology | 0.067 | Read code ever recorded | |
| EPI155 (MEDCODES) | Epilepsy (currently treated) | We have adopted the 2014 readcode list list of Kontopantelis et al (5) | 0.005 | Read code ever recorded (MEDCODES) AND Any antiepileptic prescription in last 12 months (PRODCODES) | |
| EPI156 (PRODCODES) | Epilepsy (currently treated) | We have adopted the 2014 drug list list of Kontopantelis et al (6) | Read code ever recorded (MEDCODES) AND Any antiepileptic prescription in last 12 months (PRODCODES) | ||
| HEL157 (MEDCODES) | Hearing loss | List developed by Cambridge CPRD group. expanding upon the Scottish Information Services Division (ISD) terminology for hearing loss codes | 0.111 | Read code ever recorded | |
| HEF158 (MEDCODES) | Heart failure | List developed by Cambridge CPRD group. A more sensitive list, our revision based on this original list: 10.1136/bmjopen-2015-008650 (7) | 0.014 | Read code ever recorded | |
| HYP159 (MEDCODES) | Hypertension | This is the same as the QOF 2012 list, checked by Cambridge | 0.189 | Read code ever recorded | |
| IBD160 (MEDCODES) | Inflammatory bowel disease | List developed by Cambridge CPRD group, based on Scottish Information Services Division (ISD) terminology, but more senstive. | 0.01 | Read code ever recorded | |
| IBS161 (MEDCODES) | Irritable bowel syndrome | Lists developed by Cambridge CPRD group. Read codes and Drug codes to be used together | 0.079 | Read code ever recorded (MEDCOES) OR 4 or more antispasmodic prescription only in the last 12 months (PRODCODES) | |
| IBS162 (PRODCODES) | Irritable bowel syndrome | Lists developed by Cambridge CPRD group. Read codes and Drug codes to be used together | Read code ever recorded (MEDCOES) OR 4 or more antispasmodic prescription only in the last 12 months (PRODCODES) | ||
| LEA163 (MEDCODES) | Learning disability | Lists developed by Cambridge CPRD group. | 0.004 | Read code ever recorded | |
| MIG164 (PRODCODES) | Migraine | Lists developed by Cambridge CPRD group. Read codes and Drug codes to be used together We have only included acute treatments for migraines (triptans), because most migraine prophylactics are too general and are usually prescribed for other reasons (e.g. beta-blockers) | 0.004 | 4 or more prescription only medicine anti-migraine prescriptions in last year | |
| MSC165 (MEDCODES) | Multiple sclerosis | List developed by ISD, checked by Cambridge | 0.003 | Read code ever recorded | |
| PNC166 (PRODCODES) | Painful condition | Take care constructing this long term condition! The difficulty is that many pain medications can be used for other reasons. We have therefore followed the logic of Barnett et al: 'Use PNC (if 4 or more times in 12 months) OR [PNCEP (if 4 or more times in 12 months) AND NOT EPI_MEDCODES (within last 12 months)]' where PNC = Analgesics excluding migraine treatments PNCEP = Epilepsy drugs excluding benzodiazepenes | Lists developed by Cambridge CPRD group. Epilepsy drugs excluding benzodiazepenes | 0.101 | 4 or more POM analgesics in last 12 months OR ( 4 or more specified anti-epileptics in last 12 months in the absence of an epilepsy Read code ever recorded) |
| PNC167 (PRODCODES) | Painful condition | Take care constructing this long term condition! The difficulty is that many pain medications can be used for other reasons. We have therefore followed the logic of Barnett et al: 'Use PNC (if>=4 times in 12 months) OR [PNCEP (if>=4 times in 12 months) AND NOT EPI_MEDCODES (within last 12 months)]' where PNC = Analgesics excluding migraine treatments PNCEP = Epilepsy drugs excluding benzodiazepenes | Lists developed by Cambridge CPRD group. Analgesics excluding migraine treatments | 0.101 | 4 or more POM analgesics in last 12 months OR ( 4 or more specified anti-epileptics in last 12 months in the absence of an epilepsy Read code ever recorded) |
| PRK169 (MEDCODES) | Parkinson's disease | List developed by Cambridge CPRD group, based on Scottish Information Services Division (ISD) terminology. | 0.003 | Read code ever recorded | |
| PEP135 (MEDCODES) | Peptic Ulcer Disease | Also have readcodes that look like OXMIS with no events | List developed by Cambridge CPRD group, based on Khan Charlson. NB only contains things related to stomach/duodenal ulcers. 'itis', symptoms such as dyspepsia and oesophageal symptoms are discounted. | 0.021 | Read code ever recorded |
| PVD168 (MEDCODES) | Peripheral vascular disease | This is the same as the QOF 2012 list, checked by Cambridge | 0.013 | Read code ever recorded | |
| PRO170 (MEDCODES) | Prostate disorders | List developed by Cambridge CPRD group, based on Scottish Information Services Division (ISD) terminology. | 0.057 | Read code ever recorded | |
| PSO171 (MEDCODES) | Psoriasis or eczema | Lists developed by Cambridge CPRD group for Drugs and Medcodes, to be used together | 0.007 | Read code ever recorded (MEDCODES) AND 4 or more related prescriptions in last 12 months (excluding simple emollients) (PRODCODES) | |
| PSO172 (PRODCODES) | Psoriasis or eczema | Lists developed by Cambridge CPRD group for Drugs and Medcodes, to be used together | Read code ever recorded (MEDCODES) AND 4 or more related prescriptions in last 12 months (excluding simple emollients) (PRODCODES) | ||
| PSM173 (MEDCODES) | Psychoactive substance misuse (NOT ALCOHOL) | List developed by Cambridge CPRD group. | 0.015 | Read code ever recorded | |
| RHE174 (MEDCODES) | Rheumatoid arthritis, other inflammatory polyarthropathies & systematic connective tissue disorders | List developed by Cambridge CPRD group, based on Scottish Information Services Division (ISD) terminology of rheumatoid arthritis. | 0.025 | Read code ever recorded | |
| SCZ175 (MEDCODES) | Schizophrenia (and related non-organic psychosis) or bipolar disorder | List developed by Cambridge CPRD group. | 0.003 | Read code ever recorded (MEDCODES) OR Lithium ever recorded (PRODCODES) | |
| SCZ176 (PRODCODES) | Schizophrenia (and related non-organic psychosis) or bipolar disorder | List developed by Cambridge CPRD group. | Read code ever recorded (MEDCODES) OR Lithium ever recorded (PRODCODES) | ||
| STR130 (MEDCODES) | Stroke & transient ischaemic attack | List developed by Cambridge CPRD group, based on QOF 2012, including TIA but without sub-arachnoid haemorrhage codes. | 0.029 | Read code ever recorded | |
| THY179 (MEDCODES) | Thyroid disorders | List developed by Cambridge CPRD group from QOF 2012 | 0.051 | Read code ever recorded |
- Kontopantelis E, Springate D, Reeves D, Ashcroft D.M., Valderas J.M, Doran T, et al. Withdrawing performance indicators: retrospective analysis of general practice performance under UK Quality and Outcomes Framework. BMJ. 2014; 348 :g330
- Hawkins NM, Scholes S, Bajekal M, et al. Community care in England: reducing socioeconomic inequalities in heart failure. Circulation. 2012; 126: 1050–7.
- McDonald HI, Shaw C, Thomas SL, Mansfield KE, Tomlinson LA, Nitsch D. Methodological challenges when carrying out research on CKD and AKI using routine electronic health records. Kidney international. 2016; ISSN 0085-2538. DOI: https://doi.org/10.1016/j.kint.2016.04.010
- Wilson CL, Rhodes KM, Payne RA. Financial incentives improve recognition but not treatment of cardiovascular risk factors in severe mental illness. PLoS ONE. 2017. 12(6): e0179392. https://doi.org/10.1371/journal.pone.0179392.
- Kontopantelis E, Springate D.A, Reeves D, Ashcroft D.M, Rutter M, Buchan I, Doran T. Glucose, blood pressure and cholesterol levels and their relationships to clinical outcomes in type 2 diabetes: a retrospective cohort study. Diabetologia. doi: 10.1007/s00125-014-3473-8
- Barnett K, Mercer SW, Norbury M, Watt G, Wyke S, Guthrie B. Epidemiology of multimorbidity and implications for health care, research, and medical education: a cross-sectional study. Lancet. 2012; 380(9836):37–43.
- Kontopantelis E, Olier I, Planner C, et al Primary care consultation rates among people with and without severe mental illness: a UK cohort study using the Clinical Practice Research Datalink BMJ Open 2015;5:e008650. doi: 10.1136/bmjopen-2015-008650
Cambridge Charlson Code Lists
| List ID / Download Link | CONDITION | Description / Provenance | Prevalence % | Usage in Searchable Dataset |
|---|---|---|---|---|
| C01194 (MEDCODES) | CAMBRIDGE CHARLSON - AIDS | Khan 2010 (2) | Read code ever recorded | |
| C02136 (MEDCODES) | CAMBRIDGE CHARLSON - Cancer | Subset of our Cancer List (non-metastatic) | Read code first recorded in last 5 years | |
| C10137 (MEDCODES) | CAMBRIDGE CHARLSON - Cancer (Metastatic Solid Tumour) | Subset of our Cancer List (metastatic) | Read code first recorded in last 5 years | |
| C04182 (MEDCODES) | CAMBRIDGE CHARLSON - Chronic pulmonary disease | Combined list from the following lists: Asthma list (READ and/Product codes); Bronchiectasis, COPD, Pulmonary Fibrosis, Cystic Fibrosis (READ codes) | Read code ever recorded | |
| C08184 (MEDCODES) | CAMBRIDGE CHARLSON - Diabetes End Complications | Subset of our Diabetes List | 0.011 | Read code ever recorded |
| C07183 (MEDCODES) | CAMBRIDGE CHARLSON - Diabetes No Complications | Subset of our Diabetes List | 0.067 | Read code ever recorded |
| C11133 (MEDCODES) | CAMBRIDGE CHARLSON - Mild Liver Disease | Subset of our Chronic Liver Disease List | Read code ever recorded | |
| C12134 (MEDCODES) | CAMBRIDGE CHARLSON - Moderate or Severe Liver Disease | Subset of our Chronic Liver Disease List | Read code ever recorded | |
| C13185 (MEDCODES) | CAMBRIDGE CHARLSON - Myocardial Infarction | Subset of our Coronary Heart Disease List | 0.023 | Read code ever recorded |
| PUF177 (MEDCODES) | CAMBRIDGE CHARLSON - Pulmonary Fibrosis | Used as part of Chronic pulmonary disease. List developed by Cambridge CPRD group. Excludes pneumonitis and rheumatoid lung; Includes pneumoconiosis (and related, e.g. silicosis); Excludes pulmonary amyloidosis and pulmonary sarcoidosis; Includes "interstitial" lung disease where explicitly mentioned. | 0.003 | Read code ever recorded |
| CYS178 (MEDCODES) | CAMBRIDGE CHARLSON - Cystic Fibrosis | Used as part of Chronic pulmonary disease. List developed by Cambridge CPRD group. | 0.001 | Read code ever recorded |
| HEM132 (MEDCODES) | CAMBRIDGE CHARLSON - Hemiplegia | List developed by Cambridge CPRD group, based on Khan Charlson. | 0.002 | Read Code Ever Recorded |
Cambridge ChadVasc Code Lists
| CHA2DS2-VASc Item | Codelists used | Notes & Usage |
|---|---|---|
| Congestive heart failure/LV dysfunction | Heart failure -HEF158 (MEDCODES) | Read code ever recorded |
| Hypertension | Hypertension - HYP159 (MEDCODES) | Read code ever recorded |
| Diabetes mellitus | Diabetes - DIB128 (MEDCODES) | Read code ever recorded |
| Stroke/TIA/TE | Stroke & transient ischaemic attack - STR130 (MEDCODES) | Read code ever recorded. We excluded sub-arachnoid haemorrhage and thrombotic embolism (small numbers). |
| Vascular disease (prior myocardial infarction, peripheral artery disease, or aortic plaque) | Myocardial infarction - C13185 (MEDCODES) | Read code ever recordedWe excluded aortic plaque (small numbers). |
| Peripheral vascular disease - PVD168 (MEDCODES) | Read code ever recorded |
Copyright Notice
This co-morbidity taxonomy contains 38 disease or illness groupings (with one or more related code lists) and the strategies for defining them within UK primary care databases. Version 1 (July 2016) of the classification system was modified from that developed by Barnett et al (1) ; we have however omitted glaucoma (some patients of which are now included within blindness and low vision), combined relevant chronic viral hepatitis codes into chronic liver disease, and suggest combining anxiety and depression in most instances (the purpose is to avoid double-counting or overlap of similar conditions). The specific strategies for defining individual groupings have been developed either from other published studies or originally by researchers at the Primary Care Unit, University of Cambridge. Citations and acknowledgements are available. The taxonomy will be further developed with collaboration across the National School for Primary Care Research and is freely available for academic use. We would request in the spirit of collaboration that users share any suggested amendments, which will be acknowledged or cited. If you wish to share CPRD knowledge with us, including amendments, please get in touch on the contact page, or via email CPRD@medschl.cam.ac.uk
Acknowledgements
We would also like to thank the University of Manchester ClinicalCodes.org project – “An online clinical codes repository to improve validity and reproducibility of medical database research” (https://clinicalcodes.rss.mhs.man.ac.uk/)
(1) Barnett et al (2012); Epidemiology of multimorbidity and implications for health care, research, and medical education: a cross-sectional study https://doi.org/10.1016/S0140-6736(12)60240-2
(2) Khan et al (2010); Adaptation and validation of the Charlson Index for Read/OXMIS coded databases, https://doi.org/10.1186/1471-2296-11-1
(3) Lip, G. Y., et al. (2010). “Refining clinical risk stratification for predicting stroke and thromboembolism in atrial fibrillation using a novel risk factor-based approach: the euro heart survey on atrial fibrillation.” Chest 137(2): 263-272 https://doi.org/10.1378/chest.09-1584
Last updated 30th October 2022 by CPRD@Cam