Table 2b.
Primary outcomes from the articles
| Outcome | Comparison | Number of subjects (no. of primary studies) | Measure of effect (95% confidence interval) | Direction of effect |
|---|---|---|---|---|
| Near work | ||||
| Estimation of risk | More vs. less near work | 6921 (6) | OR=1.85 (1.31-2.62) | Increased risk of myopia |
| Every 1 diopter-hour more of NW per week | 3463 (5) | OR=1.02 (1.01-1.03) | Increased risk of myopia | |
| Incidence of myopia with increasing diopter-hours spent in NW | 10617 (3) | RR=1.00 (0.99-1.01) | No effect | |
| More than 3 h/day reading | 9109 (1) | HR=1.22 (0.96-1.55) | Increased risk of myopia | |
| Reading more than 2 books/week | 2103 (2) | OR=1.43-3.05 | Increased risk of myopia | |
| Close reading distance (<30 cm) and continuous reading (>30 min) | 2353 (1) | OR=2.5 (1.74-4.0) and 1.5 (1.05-2.10) | Increased risk of myopia | |
| Changes in refractive error | NA | NA | NA | NA |
| Changes in axial length | NA | NA | NA | NA |
| Proportion (%) developing myopia | NA | NA | NA | NA |
| Proportion (%) with progressive myopia | 6 h/day of reading and NW vs. control group | 117 (1) | 48.8% vs. 18.9% | Increased risk of myopia |
| Time spent in near work | ||||
| Reading time | NA Myopic vs. non-myopic children | NA 2919 (4) | MD=0.66 (0.16-1.17) | Increased risk of myopia |
| Watching television | MD = -0.22 (-0.96 to 0.51) | No effect | ||
| Computer or video games | MD=0 (-0.60 to 0.57) | No effect | ||
| Studying | MD = -0.01 (-0.60 to 0.57) | No effect |
OR: odds ratio, RR: relative risk, HR: hazard ratio, MD: mean deviation, PA: physical activity, NW: near work, TSO: time spent outdoors, NA: not available