Intra-cluster and inter-period correlation coefficients for cross-sectional cluster randomised controlled trials for type-2 diabetes in UK primary care

Table 3 Summary of the variation of practice average values from included patients from THIN database

Outcomes, median [IQR]	Practice average
Age	68.4 [66.9–69.8]
Sex, (%)	Male, 55 [53–58]
Clinical measures
HbA1c (%), median	7.05 [6.9–7.2]
Systolic blood pressure (mmHg), median	135 [132–137.5]
Diastolic blood pressure (mmHg), median	76 [74–78]
BMI (kg/m²), median	29.9 [29.2–30.6]
Total cholesterol (mmol/L), median	4.10 [3.90–4.18]
HDL cholesterol (mmol/L), median	1.18 [1.10–1.20]
Medication, (%)
Prescribed insulin	57.8 [48.0–68.6]
Prescribed other hypoglycaemic medication	29.2 [21.8–36.7]
Clinical outcomes (%)
Atrial fibrillation	0.909 [0.476–1.497]
Chronic kidney disease	0.000 [0.000–0.560]
Chronic obstructive pulmonary disease	0.708 [0.000–1.205]
Ischaemic heart disease	0.389 [0.000–0.862]
Peripheral vascular disease	0.371 [0.000–0.800]
Stroke	0.000 [0.000–0.667]

BMI body mass index, HbA1c glycosylated haemoglobin, HDL high-density lipoprotein, IQR interquartile range. Note: the average outcome value/clinical measure was calculated for each practice using mean or median as appropriate. The average practice values were then summarised across practices by the median and interquartile range

ISSN: 1745-6215