Factors determining uptake of diabetic retinopathy screening in Oxfordshire.

AIMS: To investigate variables at the demographic and primary care practice levels that influence the uptake of diabetic retinopathy screening. METHODS: Data were extracted from the management software of one screening programme for 21 797 people registered with 79 general practices. Uptake was examined by gender, age group, modality of screening (mobile unit at general practice versus high-street optometrist), and by general practice. A telephone survey of high-street optometrists provided information on the availability of screening appointments. RESULTS: Uptake was 82.4% during the study period, and was higher for men (83.2%) than for women (81.5%) (P = 0.001). Uptake varied by age group (P < 0.001), being lowest in those aged 12-39 years (67%). Uptake was higher for people invited to a general practice for screening by a mobile unit (83.5%) than for those invited for screening by a high-street optometrist (82%) (P = 0.006). After adjusting for these factors and for socio-economic deprivation score at the location of the general practice, heterogeneity in uptake rate was still observed between some practices. Our survey of optometrists indicated wide variation in the availability of time slots for screening during the week and of screening appointment provision. CONCLUSIONS: Diabetic retinopathy screening services do not achieve high uptake among the youngest or oldest age groups. Practices in the least deprived areas had the highest uptake. Variation in uptake between general practices after adjustment for individual-level variables and deprivation suggests that practice-level factors may have an important role in determining rates of screening attendance.

The effect of oxygen saturation targeting on retinal blood vessel growth using retinal image data from the BOOST-II UK Trial.

PURPOSE: Retinopathy of prematurity (ROP) is a disorder of developing retinal blood vessels in preterm infants. The purpose of this nested study was to investigate the effects of higher (91-95%) and lower (85-89%) oxygen saturation (SpO2) targeting on retinal blood vessel growth in preterm infants. METHODS: Retinal blood vessel growth in the higher (91-95%) and lower (85-89%) oxygen saturation (SpO2) targeting groups was compared. Suitable RetCam (Clarity, Pleasanton, CA, USA) images collected in the BOOST-II UK trial were used. The distances between the centre of the optic disc and the ROP ridge in the temporal and nasal retina were measured in pixel units. RESULTS: Images from 38 infants were studied, 20 from the higher SpO2 target group and 18 from the lower SpO2 target group. On average, temporal blood vessels extended further from the optic disc than nasal blood vessels, mean (standard deviation (SD)) 463.39 (55.05) pixels compared with 360.13 (44.47) pixels, respectively, P<0.0001. Temporal blood vessels extended less far from the optic disc in the higher SpO2 target group than in the lower SpO2 target group: mean (SD) 449.83 (56.16) pixels compared with 480.02 (49.94), respectively, P=0.055. Nasal retinal blood vessel measurements were broadly similar in the higher and lower SpO2 target groups; mean (SD) 353.96 (41.95) compared with 370.00 (48.82) pixels, respectively, P=0.38. CONCLUSIONS: Relatively high oxygen saturation targeting (91-95%) was associated with a trend (P=0.055) towards reduced retinal blood vessel growth in this study of preterm infants.