Table 4 Risk of bias assessment of the observational studies a
From: Screening for cervical cancer: a systematic review and meta-analysis
Cohort study | Representativeness of exposed cohort | Selection of unexposed cohort | Ascertainment of exposure | Demonstration that outcome not present at study start | Comparability of cohorts on age | Comparability of cohorts on other factors | Assessment of outcome | Adequate length of follow-up | Adequacy of follow-up cohorts | Overall scoreb |
|---|---|---|---|---|---|---|---|---|---|---|
Herbert et al. [21] | ✓ Truly representative | ✓ Same community | ✓ Secure record | ✓ Yes | ✓ Yes | No | ✓ Record linkage | ✓ Yes (3 years) | ✓ All subjects followed | 8 |
Rebolj et al. [22] | ✗ | |||||||||
Case control study | Adequate case definition | Representative cases | Selection of controls | Definition of controls | Comparability of controls on age | Comparability of controls on other factors | Ascertainment of exposure | Method of ascertainment | Non-response rate | Overall score b |
Andrae et al. [24] | ✓ Independently validated | ✓ Consecutive cases | ✓ Community controls | ✓ No history of disease | ✓ Yes | No | ✓ Secure record | ✓ Same for both groups | ✓ Same for both groups | 8 |
Aristizabal et al.[15] | ✓ Independently validated | ✓ Representative cases | ✓ Community and hospital controls | Not stated | ✓ Yes | ✓ Neighborhood | ✓ Secure record and non-blinded interview | ✓ Same for both groups | Not stated | 7 |
Berrino et al.[16] | ✓ Independently validated | ✓ Consecutive cases | Hospital controls | ✓ No history of disease | ✓ Yes | No | ✓ Secure record | ✓ Same for both groups | ✓ Same for both groups | 7 |
Clarke and Anderson [17] | ✓ Independently validated | ✓ Representative cases | ✓ Community controls | Not stated | ✓ Yes | ✓ Neighborhood and type of dwelling | ✓ Secure record and non-blinded interview | ✓ Same for both groups | Non-respondents described | 7 |
Decker et al.[25] | ✓ Independently validated | ✓ Consecutive cases | ✓ Community controls | ✓ No history of disease | ✓ | ✓ Area of residence | ✓ Secure record | ✓ Same for both groups | ✓ Same for both groups | 9 |
Hernández-Avila et al.[26] | ✓ Independently validated | ✓ Representative cases | ✓ Community controls | Not stated | ✓Yes | ✓ Age of sexual debut, # normal births, # sex partners, SES | Non-blinded interview | ✓ Same for both groups | Rate different/no designation | 6 |
Herrero et al.[18] | ✓ Independently validated | Not stated | Hospital controls | ✓ No history of disease | No | No | Non-blinded interview | ✓ Same for both groups | ✓ Same for both groups | 4 |
Hoffman et al.[27] | ✓ Independently validated | Not stated | Hospital controls | ✓ No history of disease | ✓ Yes | ✓ Race, area of residence, hospital | Interview | ✓ Same for both groups | ✓ Same for both groups | 6 |
Jiménez-Pérez and Thomas [28] | ✓ Independently validated | ✓ Consecutive cases | Hospital controls | ✓ No history of disease | ✓ Yes | ✓ Area of residence | Non-blinded interview | ✓ Same for both groups | ✓ Same for both groups | 7 |
Kasinpila et al.[38] | ✓ Independently validated | ✓ Consecutive cases | Hospital controls | ✓ No history of disease | ✓ Yes | ✓ Significant risk factors | Non-blinded interview | ✓ Same for both groups | ✓ Same for both groups | 7 |
La Vecchia et al.[19] | ✓ Independently validated | ✓ Representative cases | Hospital controls | ✓ No history of disease | ✓ Yes | No | Interview | ✓ Same for both groups | ✓ Same for both groups | 6 |
Makino et al.[29] | ✓ Independently validated | Potential for selection bias | ✓ Community controls | ✓ No history of disease | ✓ Yes | ✓ Area of residence | Self-report | ✓ Same for both groups | ✓ Same for both groups | 7 |
Miller et al.[31] | ✓ Independently validated | Potential for selection bias | Hospital controls | ✓ No history of disease | ✓ Yes | ✓ Length of membership in health program, race/ethnicity | ✓ Secure record | ✓ Same for both groups | ✓ Same for both groups | 7 |
Nieminen et al.[23] | ✓ Independently validated | ✓ Consecutive cases | ✓ Community controls | Not stated | ✓ Yes | ✓ Socio-demographics, parity, smoking | Self-report | ✓ Same for both groups | Rate different/no designation | 6 |
✓ Independently validated | ✓ Consecutive cases | ✓ Community controls | Not stated | ✓ Yes | ✓ Area of residence | ✓ Secure record | ✓ Same for both groups | ✓ Same for both groups | 8 | |
Talbott et al.[30] | ✓ Independently validated | ✓ Consecutive cases | ✓ Community controls | Not stated | ✓ Yes | ✓ Sex, race, street or neighborhood | Non-blinded interview | ✓ Same for both groups | ✓ Same for both groups | 7 |
Yang et al.[36] | Record linkage | Not stated | Hospital controls | ✓ No history of disease | ✓ Yes | No | ✓ Secure record | ✓ Same for both groups | ✓ Same for both groups | 5 |
Zappa et al.[37] | ✓ Independently validated | ✓ Consecutive cases | ✓ Community controls | Not stated | ✓ Yes | No | ✓ Secure record | ✓ Same for both groups | ✓ Same for both groups | 7 |