Semi-structured interviews

The initial and follow-up surveys were useful in assessing the implementation of the TB-STS, but they did not give much insight into the user experience. Free-text comments written in the follow-up survey suggested that to help understand how the service was being used and the benefits and barriers to the service, the experiences of those using the TB-STS could be further explored.

Semi-structured interviews were used to understand more about the public health component of the TB-STS and the overall value of the TB-STS for health protection.

Rationale for using semi-structured interviews

The process undertaken to describe the TB-STS and the initial and follow-up surveys identified some areas for more in-depth exploration. The most appropriate approach to engage directly with service users and to learn about their different experiences with the TB-STS was through semi-structured interviews that could be conducted over the phone, at a time convenient to the interviewee.

Semi-structured interviews provided an opportunity for more in-depth information to be gathered (compared to data collected from the survey); the interviewee is able to

67 influence the topic, making the process responsive to the ideas and opinions of the respondent and allowing for unanticipated issues to emerge; further questions can be asked to understand the perspective of the respondent; and it allows a more natural conversation to take place.

Data collection

Semi-structured interviews were carried out with the main TB strain typing contact at each HPU. The aim of the interviews was to explore the different processes that are employed around the country to process, disseminate and act upon strain typing information.

The main TB strain typing contact at each HPU was identified through the national and regional CIs. Using the comments from the follow-up surveys, pilot interviews were designed and carried out with the TB strain typing leads at two HPUs during October 2012 to inform the development of the semi-structured interview guide (Box 2). The interview topic guide was adapted iteratively throughout the interview process, as new topics of interest emerged. The guide included questions on how and when cluster reports are received, what the HPU does with the information in the cluster report and suggestions for improving the service.

During November and December 2012 the remaining 24 HPU leads were interviewed. Telephone interviews lasted 20-30 minutes. 17 of 24 interviews were recorded (no recording devices were available for the other seven for which notes were taken during the interviews).

68 Box 2 – Interview guide for interviews with HPU strain typing leads

Analysis

Transcripts and notes from the semi-structured interviews were analysed using a thematic analysis based on the Framework approach.206 This approach was chosen because the analysis can be based on the predefined themes from the initial and follow-up surveys, as well as allowing for new themes to emerge from the interview data. This approach includes the following steps: familiarisation with the data (i.e. reading over the transcripts and notes); developing a thematic framework; coding the transcripts according to the framework and revising the framework as more data are analysed; once all data were coded, themes and sub-themes were refined and a descriptive analysis presented. These steps were followed with a bottom-up analytical approach, so that the shape of the analysis could inform the remaining interviews. The analysis was conducted using Excel.

Interview guide for interviews with the HPU strain typing lead: 1. What is your role in the HPU? Job/profession?

a. Are you sent cluster reports (from lab and/or cluster investigators)?

b. How many people receive cluster reports (from lab and/or cluster investigator)? 2. From whom do you receive cluster reports? Labs? Cluster investigator?

3. What do you do with a cluster report? Outcome reporting form?

a. When do you receive it? Is this too early/too late/the right time to be useful to you? Who is involved in looking at it?

b. Does the information within it affect your decision making? What is it most useful for?

c. If you act on it, do you use the strain typing handbook as a guide? Are the thresholds appropriate for your area?

d. What does ‘cluster investigation’ mean to you? What does it involve? Who decides when an investigation should be launched (cluster review meetings)? e. Who does it involve? Do you use the questionnaires (why not)?

f. How much time does it take?

g. What do you do with the information?

h. How does it affect your decision making (local outbreaks identified? Helped to solve a known outbreak?)?

i. Please give examples of when it did ii. Please give examples of when it didn’t

4. Are there ways you think the service would work better or the strain typing would be more useful?

a. E.g. Would it be better if you used the strain typing when you felt you needed it, rather than you being advised by cluster investigators when to investigate? b. Are enough resources available to use the strain typing as you would wish?

69 The analysis was carried out alongside the interviews so that themes identified in the analysis could inform the remaining interviews. The themes were quality-checked, validated and discussed with the PhD supervisors and relevant members of the evaluation steering group throughout the analysis. Themes were revised where appropriate and additional themes were added when they arose. The interviews that had already been analysed were re-visited to examine how the data related to the recently added themes. Once all 26 interviews had been coded into themes, more detailed sub-themes were identified and charted. The HPUs were grouped into low (n=14), medium (n=7) and high (n=5) TB incidence areas for the analysis.