Table 1

Overview of design options considered for Natsal-4 and whether they meet data collection requirements based on available evidence

Cheaper delivery of dataMinimise sampling and response biasSufficient statistical powerDetailed questionnaire data including new topicsYoung person/ethnic boost samplesBiological
Maintain time series
1. Probability sample + interviewer-led interviewNA
2. Follow up existing probability sample survey(✕) Need to follow up for several years(✓) Need to follow up several years.(✕) Depends on survey sample size.
3. Add detailed sexual health module to existing survey(✓) Need to include for several years.(✕) Amount of detail depends on survey/sponsors.(✕) Would need separate funding.(✓) Depending on survey.(✓) Subject to agreement from survey team.(✓) For limited set of questions, depending on mode.
4. Probability-based web/telephone panel NK (✓)NK (✕)
5. Random digit dialling + telephone interviewNK (✓)NKNK (✓)NK (✕)
6. ‘Web-first’ mixed-mode surveyNK(✓) For some but not all participants.NK (✕)NK (✓)NK ()
7. Interviewer recruitment + web surveyNK (✓)NK (✕)NK (✓)NK (✓)
  • ‘(✓)’ indicates that this is possible, depending on the specific design chosen.

  • ‘NK’ indicates insufficient evidence available from other surveys.

  • ‘NK (✓)’ indicates insufficient evidence, but likely to be able to deliver or partially deliver.

  • ‘NK (✕)’ indicates insufficient evidence, but unlikely to deliver.

  • NA, not applicable; Natsal, National Surveys of Sexual Attitudes and Lifestyles.