Table 5.
Effect of treatment arms on directly observed (primary outcome) and self reported (secondary outcome) glasses use at endline. Values are numbers (percentages) unless stated otherwise
| Intervention groups | No | Wearing glasses at baseline* | Observation of wear† | Self reported wear‡ | |||||
|---|---|---|---|---|---|---|---|---|---|
| Wearing | Relative risk (95% CI)§ | Relative risk (95% CI), full model¶ | Wearing | Relative risk (95% CI)§ | Relative risk (95% CI), full model** | ||||
| Total | 3177 | 463 (15) | 1096 (34) | 1803 (57) | |||||
| Control | 1036 | 144 (14) | 266 (26) | 1 (reference) | 1 (reference) | 386 (37) | 1 (reference) | 1 (reference) | |
| Voucher | 988 | 138 (14) | 361 (37) | 1.42 (1.16 to 1.73) | 1.44 (1.19 to 1.76) | 627 (63) | 1.70 (1.49 to 1.94) | 1.72 (1.51 to 1.96) | |
| Free glasses | 1153 | 181 (16) | 469 (41) | 1.54 (1.28 to 1.85) | 1.55 (1.30 to 1.85) | 790 (68) | 1.81 (1.60 to 2.05) | 1.81 (1.61 to 2.04) | |
| No education | 1529 | 242 (16) | 508 (33) | 1 (reference) | 1 (reference) | 818 (53) | 1 (reference) | 1 (reference) | |
| Education | 1648 | 221 (13) | 588 (36) | 1.11 (0.95 to 1.31) | 1.11 (0.94 to 1.30) | 986 (60) | 1.14 (1.03 to 1.26) | 1.13 (1.02 to 1.25) | |
| Control: no education | 510 | 85 (17) | 129 (25) | 1 (reference) | 1 (reference) | 178 (35) | 1 (reference) | 1 (reference) | |
| Control: education | 526 | 59 (11) | 137 (26) | 1.11 (0.84 to 1.47) | 1.08 (0.82 to 1.42) | 209 (40) | 1.18 (0.94 to 1.49) | 1.17 (0.94 to 1.46) | |
| Voucher: no education | 492 | 76 (15) | 185 (38) | 1.51 (1.17 to 1.95) | 1.51 (1.16 to 1.96) | 301 (61) | 1.77 (1.47 to 2.14) | 1.78 (1.48 to 2.14) | |
| Voucher: education | 496 | 62 (13) | 176 (35) | 1.48 (1.08 to 2.03) | 1.50 (1.10 to 2.03) | 326 (66) | 1.94 (1.60 to 2.36) | 1.95 (1.62 to 2.36) | |
| Free glasses: no education | 527 | 81 (15) | 194 (37) | 1.48 (1.13 to 1.92) | 1.46(1.13 to 1.89) | 339 (64) | 1.86 (1.55 to 2.23) | 1.86 (1.56 to 2.21) | |
| Free glasses: education | 626 | 100 (16) | 275 (44) | 1.75 (1.35 to 2.27) | 1.74 (1.35 to 2.23) | 451 (72) | 2.08 (1.74 to 2.48) | 2.06 (1.73 to 2.44) | |
*Defined as having glasses to hand at baseline, having previously been told to bring them to school.
†Defined as wearing glasses during an unannounced examination.
‡Defined as self report of “wearing glasses for study” or “always wearing glasses.”
§Adjusted for baseline wear.
¶Including variables associated with observed wear (P<0.20) in model including baseline wear (data not shown): age (years), aware of having refractive error at baseline, refractive error, visual acuity <6/18 (eye with better vision).
**Including variables associated with self reported wear (P<0.20) in model including baseline wear (data not shown): aware of having refractive error at baseline, refractive error, visual acuity <6/18 (eye with better vision), baseline standardized math score.