1) Always ask the people who responded “no” why they didn’t use the service. While such data is not necessary to determine the indicator’s value, it can help increase the proportion of people who use the given service.
2) Ensure that the interviewers always verify (by asking additional questions) whether the respondents have used the service in which you are interested.
3) In some instances, the service is not necessarily used by the respondent only but by the household (e.g. if an extension worker comes to provide advice). In such a case, rephrase the question: “… did your household use [specify the service]?”
4) If the service is supposed to be used repeatedly, consider also assessing how often the respondent used the service so that you can measure any frequency-related changes. You have two options for how to gain the required data:
- If the respondents are likely to remember the frequency (because you are using a short recall period or because it is likely that the person only used the service a few times), you can ask: "In the past [specify the time period], how often did you use [specify the service]?"
- If the respondents are not likely to remember the frequency, ask: "Can you please tell me when you last used [specify the service]?". While it is possible that a person used the service, for example, yesterday but otherwise s/he uses it only once per year, in the total sample of respondents, such 'accidental' facts cancel each other out, and you gain more reliable frequency data than you would get if you had asked: "How often ...?".