Table 3. Methodological quality of quasi-experimental studies.
| S/N | Study ID | Q1 | Q2 | Q3 | Q4 | Q5 | Q6 | Q7 | Q8 | Q9 | Total of ‘yes’ scores |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1. | Lohinva et al. 2015 [66] | Y | Y | Y | Y | Y | N | Y | Y | Y | 8 |
| 2. | Norr et al. 2012 [62] | Y | Y | Y | Y | Y | Y | Y | Y | Y | 9 |
| 3. | Pulewitz et al. 2015 [64] | Y | Y | Y | Y | Y | N | Y | Y | Y | 8 |
| 4. | Williams et al. 2006 [61] | Y | Y | Y | N | Y | U | Y | Y | Y | 8 |
| 5. | Zachariah 1998 [67] | Y | Y | Y | N | Y | Y | Y | Y | Y | 8 |
NB: Y = Yes, U = unclear, NA = not applicable
Q1. Is it clear in the study what is the ‘cause’ and what is the ‘effect’ (i.e. there is no confusion about which variable comes first)?
Q2. Were the participants included in any comparisons similar?
Q3. Were the participants included in any comparisons receiving similar treatment/care, other than the exposure or intervention of interest?
Q4. Was there a control group?
Q5. Were there multiple measurements of the outcome both pre-and post the intervention/exposure?
Q6. Was follow up complete and if not, were differences between groups in terms of their follow up adequately described and analyzed?
Q7. Were the outcomes of participants included in any comparisons measured in the same way?
Q8. Were outcomes measured in a reliable way?
Q9. Was appropriate statistical analysis used?