Network Sampling of Hard-to-Reach Population: An Application to the Substance Abuse Problem Among Tertiary Education Students in Nigeria

Traditional sampling techniques have not yielded desired results when applied to hidden or rare populations. A hidden population of considerable interest in Nigeria is that of students in tertiary institutions engaged in substance abuse because of the stigma surrounding such habits and the high heath-risk they constitute to both themselves and the communities where they are found. Earlier works on the subject have concentrated on descriptive approaches. This paper uses the Horvitz-Thompson network sampling technique to estimate the proportion of students in tertiary institutions in Lagos who partake in substance abuse.