Estimating number of users based on number of deaths
One method for estimating the number of injecting drug users in a country, is to multiply the number of deaths from overdose with a constant: number of users = konstant * number of overdose deaths or: nu = k * nod The intuition is simple. In any given year a fixed share of the drug users will dive from overdose, and this means that we can multiply the number of deaths by a constant to get the total number of users. For instance, assume the probability of dying from overdose is 1% in a given year. If 100 people dies, this means that there are 10 000 users. Note that the constant in the calculation (k) is one divided by the probability of experiencing death from an overdose for a random user. k=1/pu It is important to note this because typically p is very small. Compared to the total number of drug users, relatively few people die from an overdose every year. This means that k is very sensitive to small changes in the estimated probability of death from overdose. This, in