A baseline comparison between the intervention and control groups
| Baseline comparison between the intervention and control groups | Control group (further laser) (n = 21) | Intervention group (vitrectomy) (n = 19) | ||
|---|---|---|---|---|
| No (% or SD) | No (% or SD) | |||
| *IQR, interquartile range. | ||||
| Age (years) | 64.2 (9.98) | 64.3 (10.69) | ||
| Sex | Female | 6 (29%) | 8 (42%) | |
| Male | 15 (71%) | 11 (58%) | ||
| Ethnicity | Afro-Caribbean | 1 (5%) | 0 (0%) | |
| White | 19 (90%) | 18 (95%) | ||
| Indian | 1 (5%) | 1 (5%) | ||
| Type of diabetes | Type 1 | 2 (10%) | 1 (5%) | |
| Type 2 | 19 (90%) | 18 (95%) | ||
| Insulin controlled | Yes | 11 (52%) | 15 (79%) | |
| Blood pressure (mm Hg) | Systolic | 140 (16) | 136 (14) | |
| Diastolic | 77 (11) | 77 (9) | ||
| HbA1c% | 7.7 (1.4) | 8.8 (1.5) | ||
| Serum creatinine (mmol/l) | 108.5 (41.6) | 103.2 (32.5) | ||
| Median duration of diabetes (years) [IQR*] | 11 8,16 | 14.5 10,20 | ||
| Past history of laser treatment | Heavy macular laser (>300 burns) | 14 | 12 | |
| Moderate macular laser (126–300 burns) | 5 | 4 | ||
| Light macular laser (<126 burns) | 2 | 3 | ||
| Panretinal photocoagulation | 3 | 4 | ||
| ETDRS logMAR visual acuity mean (SD) | 0.60 (0.23) | 0.65 (0.28) | ||
| OCT central macular thickness (μm) median [IQR] | 403 [337, 492] | 387 [298, 491] | ||
| Median central nuclear density (%) [IQR] | 33.05 [30.0, 42.5] | 33.85 [29.6, 49.0] | ||