Bulletin of the World Health Organization

Determining health-care facility catchment areas in Uganda using data on malaria-related visits

Kate Zinszer, Katia Charland, Ruth Kigozi, Grant Dorsey, Moses R Kamya & David L Buckeridge

Volume 92, Number 3, March 2014, 178-186

Table 1. Cumulative rate of confirmed malaria cases at six health-care facilities in Uganda,a by catchment area definition, 2012

Catchment area definition Cumulative rate of confirmed malaria cases, CCR (95% CI)b
Aduku facility Kamwezi facility Kasambya facility Kihihi facility Nagongera facility Walukuba facility
Straight-line distance,c km
5 89.2 (82.0–97.0) 234.9 (226.2–243.8) 218.3 (211.6–225.1) 121.9 (117.5–126.4) 119.9 (115.7–124.3)       20.3 (19.6–20.1)
10 45.9 (43.7–48.2) 71.8 (69.3–74.3) 116.2 (112.9–119.6) 59.2 (57.3–61.1) 43.4 (42.1–44.7)       14.8 (14.3–15.3)
20 13.3 (12.8–14.0) 22.0 (21.2–22.8) 39.5 (38.4–40.7) 21.3 (20.7–22.0) 12.1 (11.7–12.4)       8.2 (7.9–8.5)
30 7.2 (6.8–7.5) 8.2 (7.9–8.5) 21.8 (21.2–22.5) 11.0 (10.7–11.4) 6.1 (5.6–6.7)       4.8 (4.6–5.0)
Road network distance,d km
5 0 (NA) 156.1 (150.9–161.4) 218.3 (211.6–225.1) 128.9 (124.3–133.6) 143.3 (137.8–148.9)       5.5 (5.1–6.1)
10 48.5 (46.0–51.1) 130.0 (125.6–134.5) 218.3 (211.6–225.1) 81.1 (78.6–83.8) 49.3 (47.8–50.9) 22.9 (22.2–23.7)
20 17.6 (16.8–18.5) 45.8 (44.2–47.4) 49.0 (47.7–50.5) 41.6 (40.3–43.0) 17.2 (16.7–17.7) 11.9 (11.5–12.3)
30 11.7 (11.2–12.2) 32.0 (30.9–33.2) 33.0 (32.0–33.9) 22.8 (22.1–23.5) 9.0 (8.7–9.2) 7.5 (7.3–7.8)
Cumulative case ratioe 38.1 (36.3–40.0) 193.1 (186.8–199.6) 67.2 (65.3–69.1) 87.6 (84.0–90.3) 38.4 (37.3–39.6) 43.3 (41.9–44.7)

CCR, cumulative case rate; CI, confidence interval; NA, not applicable.

a Data on the health-care facilities were collected by the Uganda Malaria Surveillance Project.

b Per 1000 population.

c Catchment areas were defined as lying within a specified straight-line distance from the facility.

d Catchment areas were defined as lying within a specified road network distance from the facility.

e A parish was included in the catchment area if the upper limit of the 95% CI for the cumulative case ratio for the parish (i.e. the ratio of observed to expected malaria-related visits from the parish) was 1 or greater.