eTable 3. Risk of bias within studies.
| Reliability of instruments | k*1 | % |
| Acceptable reliability/low risk | 40 | 42.1 |
| Questionable reliability/high risk | 9 | 9.5 |
| Insufficient information/unclear risk | 46 | 48.4 |
| Incomplete reporting | n*2 | % |
| Satisfactory reporting/low risk | 46 | 83.6 |
| Incomplete reporting/high risk | 9 | 16.4 |
| i*3 | M (SD) | |
| Response rate | 43 | 0.70 (0.24) |
*1 reported for associations, *2 reported for studies, *3 reported for samples; for i = 14 samples no information available
M = mean; SD = standard deviation