|Risk of bias item||Response: Yes (Low Risk) or No (High risk)|
|1. Was the study target population a close representation of the national population in relation to relevant variables?|
|2. Was the sampling frame a true or close representation of the target population?|
|3. Was some form of random selection used to select the sample, OR, was a census undertaken?|
|4. Was the likelihood of non-participation bias minimal?|
|5. Were data collected directly from the subjects (as opposed to medical records)?|
|6. Was an acceptable case definition used in the study?|
|7. Was the study instrument that measured the parameter of interest (e.g. prevalence of adolescent pregnancy) shown to have reliability and validity (if necessary)?|
|8. Was the same mode of data collection used for all subjects?|
|9. Was the length of the shortest prevalence period for the parameter of interest appropriate?|
|10. Were the numerator(s) and denominator(s) for the calculation of the prevalence of adolescent pregnancy appropriate?|
11. Summary item on the overall risk of study bias|
Low Risk of Bias: 8 or more “yes” answers. Further research is very unlikely to change our confidence in the estimate.
Moderate Risk of Bias: 6 to 7 “yes” answers. Further research is likely to have an important impact on our confidence in the estimate and may change the estimate.
High Risk of Bias: 5 or fewer “yes” answers. Further research is very likely to have an important impact on our confidence in the estimate and is likely to change the estimate