Table 6 Checklist used for the assessment of the methodological quality of the included studies
From: Does total hip replacement affect sexual quality of life?
Theoretical background | Used for selection bias |
1. Is there a theoretical background for the hypothesis? | |
Study participation | |
2. Is the study population clearly described in terms of age, gender, and important patients’ characteristics? | Used for selection bias |
3. Is the percentage of eligible subjects who participated in the study (response rate) adequate? (More than 30 % is considered inappropriate) | Used for selection bias |
Sampling | |
4. Are patients who participated in the study similar to eligible non-participants (the population), in terms of age, gender, and important disease characteristics? | Used for selection bias |
Study attrition | |
5. Is the percentage of subjects available for analysis adequate? (<30 % not too many missing values or loss to follow-up)? | Used for selection bias |
6. Were reasons for loss to follow-up presented and assessed during the study for possible systematic attrition? (Subjects that did not finish the study) | Used for selection bias |
Outcome measurement | |
Definition of outcome variable(s) | Used for information bias |
7. Are clear definitions of each outcome variable provided? | |
8. Is clear operationalization of each outcome variable provided? How is it measured? | Used for information bias |
Measurement of outcome variable(s) | Used for information bias |
9. Are the measurement instruments used for the measurement of the outcome variable(s) reliable and valid? | |
Method and setting of the outcome variable(s) | Used for information bias |
10. Were the measurement approach, time and place of measurement of the outcome variable(s) standardized or conducted in a way that limits systematically different measurement? | |
Study confounding | |
Definition of potential confounders | Used for information bias |
11. Are clear definitions of each confounder provided? | |
12. Is clear operationalization of each confounder provided? | Used for information bias |
Measurement of potential confounders | Used for information bias |
13.Are the measurement instruments used for the measurement of the confounder(s) reliable and valid? | |
Method and setting of the confounder(s) | Used for information bias |
14. Were the measurement approach, time and place of measurement of the confounder(s) standardized or conducted in a way that limits systematically different measurement? | |
Statistical analyses | |
15. Is the percentage of missing values adequate? Less < 30 % | Used for statistical analysis bias |
16. Were multivariable analyses performed? Yes is rated as “0” if yes | Used for statistical analysis bias |
17. Was it clearly described which variables were included in the (multivariable) model(s)? | Used for statistical analysis bias |