Participants

Adult participants with BN, 12 in total, were recruited originally from the outpatient department of a large Eating Disorder Service in London between 2014 and 2016. Demographic information is provided in Table 1. Participants were included if they were over 18 and had a clinical diagnosis by the senior author (PR), using DSM-5 criteria, of BN for at least 5 years continuously. The number of participants was estimated based on the advice of Guest et al. [10] that for most qualitative studies, 12 was a reasonable number of participants. We therefore approached 12 participants and all agreed. Each participant was interviewed after reading an information sheet, then signing a hard copy consent form at least 24 h later, having had that time to ask questions. Interviews took place in a quiet room in the clinical unit and each was audio recorded and then transcribed. Recordings were labelled with a research ID unrelated to the participants’ names or initials and kept on a secure folder on the Hospital Trust computer system and securely deleted as soon as the transcripts had been checked for accuracy, within 10 days of recording. Only the interviewer and the senior research (PHR) had access to the recordings. In this report participants’ initials have been changed to preserve anonymity.

Table 1 Demographic information on 12 participants with longstanding Bulimia NervosaInterviews

Interviewers were all the co-authors apart from PHR who convened the other co-authors in qualitative discussion groups. Each of the 5 interviewers saw 2 or 3 of the participants. All interviewers were Masters students at University College London and held an honorary contract with the mental health trust where the participants were being treated. They were not involved in treatment of the participants. The interviewers interviewed the participants with the help of a topic guide (see Table 2) with questions that covered areas around physical, psychological, family, occupation, accommodation, finances, relationships, and social realms. The topic guide was developed from content in “Severe and Enduring Eating Disorders” [18]. However, the topic guide was used flexibly and interviewers were free to explore aspects of participants’ lives as they felt was appropriate according to the issues that the participant was sharing.

Table 2 Starting questions in each realm in the research interviews

The questions were kept open-ended with minimal interruption by the interviewer. Participants were asked to describe their experiences and interviewers responded by asking further open questions until the matter being discussed had been as fully described as possible. The duration of the interviews ranged between forty minutes and two hours. Interviews were recorded and transcribed.

Analysis

Each of the interview transcripts was analysed using thematic analysis [4]. The specific form of TA was Reflexive Thematic Analysis. “Reflexive thematic analysis is considered a reflection of the researcher’s interpretive analysis of the data conducted at the intersection of: (1) the dataset,(2) the theoretical assumptions of the analysis, and; (3) the analytical skills/resources of the researcher [3].” (From Byrne [7]. This approach was chosen as we required a flexible approach, not tied to a specific theoretical framework, that could be extended to larger sample sizes.

Braun and Clarke [2, 4] list the characteristics of this approach as:

1.

Dataset familiarisation

2.

Rigorous and systematic coding

3.

Exploring, developing and refining themes

4.

Producing the analytic report

While the realms were predetermined, came from the researchers’ experience of treatment of eating disorders, and therefore followed a deductive paradigm, coding, themes and interpretation were all carried out inductively without prior assumptions. The researchers also used some elements of phenomenology in that the subjective experience of participants was explored.

Quotes from the interviews were transferred to an Excel spreadsheet and given initial open codes that briefly described the quote. These initial open codes were further classified into selective codes that serve the purpose of capturing common patterns within the original realms of the interview guide. The selective codes were then grouped together under each realm, and a descriptive memo was created for each of the realms. A general narrative was then written about each participant which included their general experience, emerging themes and the researcher’s interpretation. Common patterns and themes were then compared between different participants in order for conclusions to be made between groups. Codes, memos, themes and narratives were discussed regularly in a qualitative analysis meeting with at least the interviewer/analyst and the senior researcher (PHR). The process is illustrated in Fig. 1.

Fig. 1

Illustrating the process used to analyse interview transcripts in the study

Relationship between the contributions of the individual researcher and the group

Each researcher analysed the data obtained in the interviews and their transcripts drawing on their own theoretical assumptions and their own particular skills (see above quote from Byrne [7]. At the QA meeting noted above, researchers and the senior researcher (PHR) met to discuss the quotes, codes and themes and came to agreement on each analysis going forward.