Question

Part 7 Several countries in Africa have implemented a programme to supply insecticide- treated bed nets to communities in which there was a high prevalence of malaria in young children. A study was carried out to estimate the impact of the programme and determine whether the prevalence of malaria in young children was lower in countries that had implemented the programme. Researchers randomly sampled households from a country that had implemented the programme (country A) and a country that had not implemented the programme (country B) and collected data on the number of children aged under 2 with malaria. Diagnosis of malaria was done using rapid diagnostic tests (RDTs) which detect specific antigens (proteins) produced by malaria parasites in the blood of infected individuals. Blood for the test was obtained from a finger-prick. Nurse researchers visited the household to carry

Answer 1

1. The study design used in this case is case - control design and the samples are selected by random sampling . The question is comparing the prevalence of malaria in people who had insecticide treated net and those who don't had insecticide treated net . For comparison purpose ,this study design is appropriate .

2. Prevalence of malaria in country A :

Total number of cases in country A with malaria = 210

Total number of samples taken from country A = 842

Prevalence rate = 210/842 ×1000

= 24.9%

Prevalence of malaria in country B:

Total number of cases in country B with malaria = 309

Total number of samples taken from country B= 853

Prevalence rate = 309/853× 1000

= 36.2 %