Colorectal (Collins and Altman, 2012)38 Primary care, UK | Cohort THIN database 01/01/00–30/06/08 2 years following entry | Weight loss Read code Relevant cancer Read code | THIN record, starting latest of, study start date, registration, first symptom | Prior colorectal cancer; GP registered <12 months, invalid dates, <30/≥85 years |
Colorectal (Curless et al, 1994) 57 Primary and secondary care, North East England | Case–control (1:1) Structured patient questionnaire 01/1989–30/09/90 1 year pre-diagnosis | Patient reported ‘subjective weight loss’ Histological diagnosis of cancer | Cases: consecutive cases identified within <2 weeks of diagnosis by hospital surgical residents Controls: patients adjacent on GP register for age and sex | Prior colorectal cancer or inflammatory bowel disease, ‘non-white’, death (n = 15), outside area (n = 10), no consent (n = 2), unclear diagnosis (n = 1), GP advised against (n = 4), refused (n = 43), unable to contact (n = 6) |
Colorectal (Hamilton et al, 2005) 55 Primary care, Exeter, England | Case–control (1:5) GP record (written and electronic) 1998–2002 (diagnosis) 2 years pre-diagnosis | Any mention of weight loss in GP record Cancer registry, histology reports, and specialist case records | Cases: identified by local cancer registry, histology reports, or specialist diagnosis Controls: practice, sex, and age matched to cases, and alive at index diagnosis | Unobtainable records (n = 96), no entry in the records in 2 years pre-diagnosis (n = 111), prior colorectal cancer (n = 32), lived outside Exeter at diagnosis (n = 22) |
Colorectal (Hamilton et al, 2009) 8 Primary care, UK | Case–control (1:7) THIN database 01/2001–07/2006 (diagnosis) 2 years pre-diagnosis | Difference between last recorded weight and highest weight in previous 2 years (≥10% or 5–10% weight loss) Cancer recorded in THIN | Cases: THIN code for colorectal cancer Controls: practice, sex, year of birth matched | Prior colorectal cancer, <2 years of records before the index date |
Colorectal (Hippisley-Cox and Coupland, 2012)48 Primary care, UK | Cohort QResearch database 01/01/00–30/09/10 2 years following entry | Weight loss code UK diagnostic code in GP record and ONS cause of death ICD-9 (153 or 154) or ICD-10 (C18–C21) codes | EMIS record, starting latest of, study start date, 12 months after practice registration, first recorded loss rectal bleeding, loss of appetite, weight loss, or abdominal pain | No Townsend score (n = 195 305). Prior colorectal cancer (n = 8414). Rectal bleeding, loss of appetite, weight loss, or abdominal pain in prior 12 months (n = 89 572) |
Gastro-oesophageal (Collins and Altman, 2013)41 Primary care, UK | Cohort THIN database 01/01/00–30/06/08 2 years following entry | Weight loss Read code Relevant cancer Read code | THIN record, starting latest of, study start date, registration, first red-flag symptom of gastro-oesophageal cancer | Prior gastro-oesophageal cancer, GP registered <12 months, invalid dates, <30/≥85 years |
Gastro-oesophageal (Hippisley-Cox and Coupland, 2011)45 Primary care, UK 2 years following entry | Cohort QResearch database 01/01/00–30/09/10 or ICD-10 (C15 or C16) codes | Weight loss code UK diagnostic code in GP record and ONS cause of death ICD-9 (150 or 151) | EMIS record, starting latest of, study start date, 12 months after practice registration, first recorded dysphagia, haematemesis, appetite loss, weight loss, or abdominal pain | No Townsend score (n = 195 305). Gastro-oesophageal cancer (n = 1377). Dysphagia, haematemesis, loss of appetite, weight loss, and abdominal pain in prior 12 months (n = 89 572) |
Gastro-oesophageal (Stapley et al, 2013) 53 Primary care, UK | Case–control (1:5) CPRD database 01/2000–12/2009 >1 year pre-diagnosis | GP weight loss Read code 24 gastric and 18 oesophageal Read codes | Cases: gastro-oesophageal cancer code Controls: age, sex, and practice matched | No records<1 year before index date (n = 3335), metastatic cancer (n = 10), cases with past gastrooesophageal cancer (n = 28), cases without controls (n = 17), oesophageal cancer used as gastric (n = 131), controls are cases (262), controls without cases (809), duplicate control (n = 427) |
Lung (Hamilton et al, 2005) 54 Primary care, Exeter, England | Case–control (1:5) GP record (written and electronic) 1998–2002 (diagnosis) 2 years pre-diagnosis | Any mention of weight loss in GP record Cancer registry, histology reports, and specialist case records | Cases: identified by local cancer registry, histology reports, or specialist diagnosis Controls: practice, sex, and age matched to cases, and alive at index diagnosis | Unobtainable records (n = 77), no records in 2 years pre-diagnosis (n = 98), prior lung cancer (n = 9), lived outside Exeter at diagnosis (n = 15), unconfirmed or atypical (n = 28), metastatic cancer unknown origin (n = 7) |
Lung (Iyen-Omofoman et al, 2013) 43 Primary care, UK | Case–control (1:10) THIN database 01/01/00–28/07/09 4–24 months pre-diagnosis | GP weight loss code Cancer recorded in THIN | Cases: THIN code for lung cancer Controls: practice matched to cases | <1 year of records prior to lung cancer diagnosis, <40 years at index diagnosis (n = 59) |
Multiple, male (Hippisley-Cox and Coupland, 2013)22 Primary care, UK | Cohort QResearch database 01/01/00–01/04/12 2 years following entry | Weight loss code UK diagnostic code in GP record and ONS cause of death ICD-9 or ICD-10 code | EMIS record for at least a year | No Townsend score (n = 124 743). Red-flag symptom in the 12 months prior to study entry (n = 91 819) |
Multiple, female (Hippisley-Cox and Coupland, 2013)23 Primary care, UK | Cohort QResearch database 01/01/00–01/04/12 2 years following entry | Weight loss code UK diagnostic code in GP record and ONS cause of death ICD-9 or ICD-10 code | EMIS record for at least a year | No Townsend score (n = 132 945). Red-flag symptom in the 12 months prior to study entry (n = 165 310) |
Myeloma (Shephard et al, 2015) 50 Primary care, UK | Case–control (1:5) CPRD database 01/2000–12/2009 >1 year pre-diagnosis | GP weight loss Read code 23 myeloma Read codes | Cases: multiple myeloma code Controls: age, sex, and practice matched | No records <1 year before index date (n = 1201), cases without controls (n = 1), controls with myeloma (n = 8), controls with no record after registration (n = 13), cases with para-proteinaemia >60 days before myeloma code (n = 26), control of para-proteinaemia case |
Non-Hodgkin’s lymphoma (Shephard et al, 2015) 51 Primary care, UK | Case–control (1:5) CPRD database 01/2000–12/2009 >1 year pre-diagnosis | GP weight loss Read code 106 non-Hodgkin’s lymphoma (nHL) Read codes | Cases: nHL code Controls: age, sex, and practice matched | Hodgkin’s lymphoma (HL) (n = 283), control of HL (n = 1402), case of mycosis fungoides or Sézary syndrome (n = 147), control of mycosis fungoides or Sézary syndrome (n = 719); no records <1 year before index date (2018); cases without controls (7); controls with non-HL (n = 70); controls with no record after registration (n = 26) |
Ovarian (Collins and Altman, 2013) 42 Primary care, UK | Cohort THIN database 01/01/00–30/06/08 2 years following entry | Weight loss Read code Relevant cancer Read code | THIN record, starting latest of, study start date, registration, first red-flag symptom of ovarian cancer | Prior ovarian cancer, GP registered <12 months, invalid dates, <30/≥85 years |
Ovarian (Hippisley-Cox and Coupland, 2012)46 Primary care, UK | Cohort QResearch database 01/01/00–30/09/10 2 years following entry | Weight loss code UK diagnostic code in GP record and ONS cause of death ICD-9 codes (183) or ICD-10 (C56) codes | EMIS record, starting latest of, study start date, 12 months after practice registration, first recorded loss of appetite, weight loss, abdominal pain, abdominal distension, rectal bleeding, or post-menopausal bleeding | No Townsend score (n = 98 260). Prior bilateral oophorectomy (n = 21 099) or ovarian cancer (n = 2079). Loss of appetite, weight loss, abdominal pain, abdominal distension, rectal bleeding, or post-menopausal bleeding in prior 12 months (n = 55 824) |
Ovarian (Lim et al, 2012) 59 Ovarian cancer population study, UK | Case–control (1:1.2) Questionnaire, telephone interview, ‘GP notes’ 16/02/06–28/02/08 15 months pre-diagnosis | Unplanned weight loss, including the appearance of weight loss (questionnaire, telephone interview, or GP code) Independent review of staging, histology, pathology, and case notes by gynae-oncologist | Cases: 50–79 years, attending preoperative or medical oncology clinic, or admitted for surgery for primary ovarian cancer Controls: attending ovarian screening (post-menopausal) clinic, or surgery for a suspected benign adnexal mass | Differential agreement to take part in questionnaire and telephone studies |
Pancreatic (Collins and Altman, 2013)40 Primary care, UK | Cohort THIN database 01/01/00–30/06/08 2 years following entry | Weight loss Read code Relevant cancer Read code | THIN record starting latest of study start date, registration, first red-flag symptom of pancreatic cancer | Prior pancreatic cancer; GP registered <12 months, invalid dates, <30/≥85 years |
Pancreatic (Hippisley-Cox and Coupland, 2012)49 Primary care, UK | Cohort QResearch database 01/01/00–30/09/10 2 years following entry | Weight loss code UK diagnostic code in GP record and ONS cause of death ICD-9 (157) or ICD-10 (C25) codes | EMIS record, starting latest of, study start date, 12 months after practice registration, first recorded dysphagia, loss of appetite, weight loss, abdominal pain, or distension | No Townsend score (n = 195 305). Prior pancreatic cancer (n = 257). Dysphagia, loss of appetite, weight loss, abdominal pain, or abdominal distension in prior 12 months (n = 77 071) |
Pancreatic (Holly et al, 2004) 58 San Francisco Bay ‘population’ | Case–control Two questionnaires by interview 1994–2001 5 years pre-diagnosis | Patient reported weight loss of >6 weeks’ duration Surveillance, Epidemiology, and End Results (SEER) database 18–24 months after diagnosis | Cases: pancreatic cancer identified within 1 month of diagnosis by north California cancer centre rapid case ascertainment Controls: random digit dial age (+/− 5 years) and sex matched (healthcare financing data supplemented recruitment >65 years) | Incomplete second questionnaire, non-English speaker, deceased |
Pancreatic and biliary tree (Keane et al, 2014) 44 Primary care, UK | Case–control (1:6) THIN database 01/01/00–31/12/10 2 years pre-diagnosis | GP weight loss code Cancer recorded in THIN | Cases: GP practices with acceptable mortality recording and computer usage Controls: stratified sampling within practice matched by age, sex, year of consultation (controls), or diagnosis (cancer) | <2 years of data prior to the index date |
Pancreatic (Stapley et al, 2012) 52 Primary care, UK | Case–control (1:5) CPRD database 01/2000–12/2009 >1 year pre-diagnosis | GP weight loss Read code 25 pancreatic cancer Read codes | Cases: pancreatic cancer code Controls: age, sex, and practice matched | Cases without controls (n = 2), not a pancreatic primary (n = 10), controls with pancreatic cancer (n = 64), controls no case (n = 40), controls with no data in the year before diagnosis the index date (n = 1414) |
Prostate (Hamilton et al, 2006) 56 Primary care, Exeter, England 1998–2002 (diagnosis) | Case–control (1:5) GP record (written and electronic) 2 years pre-diagnosis | Any mention of weight loss in GP record Cancer registry, histology reports, and specialist case records | Cases: identified by local cancer registry, histology reports, or specialist diagnosis Controls: practice, sex, and age matched, and alive at index diagnosis | Unobtainable records (n = 82), no entry in the records in 2 years pre-diagnosis (n = 83), prior prostate cancer (n = 27), lived outside Exeter at diagnosis (n = 26), other/unconfirmed (n = 5) |
Renal tract (Collins and Altman, 2013)39 Primary care, UK | Cohort THIN database 01/01/00–30/06/08 2 years following entry | Weight loss Read code Relevant cancer Read code | THIN record, starting latest of, study start date, registration, first red-flag symptom of renal tract cancer | Prior renal tract cancer; GP registered <12 months, invalid dates, <30/≥85 years |
Renal tract (Hippisley-Cox and Coupland, 2012)47 Primary care, UK | Cohort QResearch database 01/01/00–30/09/10 2 years following entry | Weight loss code UK diagnostic code in GP record and ONS cause of death ICD-9 (188 or 189) or ICD-10 (C64–67) codes | EMIS record, starting latest of, study start date, 12 months after practice registration, first recorded loss of haematuria, appetite loss, weight loss, or abdominal pain | No Townsend score (n = 195 305). Prior renal tract cancer (n = 4417). Haematuria, loss of appetite, weight loss, or abdominal pain in prior 12 months (n = 81 332) |