Table 3.
Main findings of the sub-group analyses, showing the statistically significant impact on the prevalence rate of sleep disturbances of methodological quality of studies included, sample size, and region where the studies were conducted.
| Variables | Number of Studies | Number of Participants | Prevalence Rate and 95%CI | I2 | Statistical Significance (p-Value) |
|---|---|---|---|---|---|
| Methodological quality of the studies included | |||||
| 1–8 (weak quality) | 3 | 397 | 50% (41–60) | 73.3% | 0.000 |
| 9–16 (moderate quality) | 5 | 1219 | 59% (30–88) | 99.44% | 0.000 |
| 17–22 (good quality) | 9 | 1970 | 59% (43–75) | 98.4% | 0.000 |
| Sample sizes of the studies included | |||||
| Less than 200 participants | 9 | 1144 | 63% (52–74) | 94% | 0.000 |
| More than 200 participants | 8 | 2442 | 52% (31–72) | 99.3% | 0.000 |
| Region where the studies included were conducted | |||||
| North | 4 | 785 | 75% (22–91) | 99.2% | 0.000 |
| West | 6 | 1006 | 58% (41–74) | 97% | 0.000 |
| East | 5 | 1290 | 52% (32–71) | 98.3% | 0.000 |
| South | 2 | 505 | 75% (48–93) | 95.9% | 0.000 |
CI: confidence interval; I2: heterogeneity.