General Aims:
This pilot RCT aims to assess the feasibility and acceptability of a muscle relaxation intervention with guided imagery (experimental group - GE) compared to a neutral guided imagery placebo (active control group - ACG) and a group that does not receive any psychological intervention (passive control group - PCG), prior to the implementation of a future definitive RCT that will assess its effectiveness.
This study will also examine, qualitatively, the perspectives of patients with DFU regarding the relaxation intervention, in order to check its acceptability and applicability; as well as the perspectives of health professionals on this adjuvant therapy, its applicability and integration into the multidisciplinary team of diabetic foot consultations.
Pilot RCT specific aims:
1. To evaluate the rates of eligibility, recruitment and adherence to the study protocol, participation in follow-up, and withdrawal. The degree of patient satisfaction with the relaxation intervention will also be assessed.
2. To verify the feasibility of the assessment protocol and to obtain preliminary estimates of the effects of the intervention on health outcome measures (degree of DFU healing, DFU-related quality of life, anxiety, depression and stress, DFU representations and physical and mental quality of life);
3. Synthesize the information to estimate the sample size required for a future definitive RCT.
Qualitative study nested in Pilot RCT specific aims:
4. To understand the perspective of patients and health professionals about the relaxation sessions;
5. To explore the contribution of the relaxation sessions to the DFU healing and patients' quality of life;
6. To describe the changes perceived in the patient during the period of relaxation sessions;
7. To analyse the relevance of implementing relaxation sessions in the multidisciplinary team consultation of diabetic foot.
Data Analysis:
To assess the feasibility of this pilot study (aim 1), the rates of eligibility, recruitment and adherence to the study protocol, participation in the follow-up and withdrawal will be calculated and its results will be presented in percentage. The results of the degree of satisfaction with the intervention will be presented through mean and standard deviation. To obtain preliminary estimates of the intervention effects' on health outcome measures (aim 2), descriptive measures of the respective variables (means and standard deviations) will be calculated and Generalised Mixed Models will be used to check for statistically significant differences over time, in the different groups. Data will be analysed using IBM SPSS Statistics 26 for Mac. Finally, from the data obtained, the sample size for a future definitive RCT will be calculated (aim 3).
To answer the aims 4 to 7, a semi-structured interview guide consisting of open-ended questions will be administered to patients with DFU that benefited from the relaxation sessions and to the health professionals who provided them the DFU care. This script will remain unchanged throughout the interviews. The audio recording of the interviews will be done using a tablet, transcribed verbatim and anonymised in order to safeguard participants and data confidentiality. The transcripts of the interviews will be analysed in the same order as conducted, using the thematic content analysis technique (Bardin, 2016).
Sample size calculation:
The sample size calculation for a pilot RCT, considering the average effect size of 0.5, a statistical power of 80% and a significance level of 5%, revealed that 12 participants were needed in each of the groups (Cocks \& Torgerson, 2013). This approach considers that a one-sided 80% confidence interval for the effect size will exclude the minimum clinically significant difference if the null hypothesis is true (Brown \& Lilford, 2006).
Procedure:
The doctor or nurse, in the medical appointment, identifies patients that meet the medical inclusion criteria. Patients are invited to participate in the study by the Researcher at the end of the medical appointment and are informed about the aims of the study and the voluntary nature of participation through informed and informative consent. If patients agree to participate, they will sign the consent form. Nurses will then complete RESVECH 2.0 at the end of the appointment and doctors will complete the clinical questionnaire. Afterwards, the Researcher will accompany the patient to a room provided by the Hospital in order to administer the battery of questionnaires in the interview format.
After answering the questionnaires, the researcher will score the PSS and HADS instruments to identify the presence of significant clinical levels of stress, anxiety and depression, and if the patient is eligible, at the end of that week, the participant will be randomized into one of three possible groups.
In the next diabetic foot appointment, the respective participant will be informed about the group to which he or she has been allocated and whether will benefit, if appropriate, from four sessions of relaxation (EG) or neutral guided imagery (ACG), depending on the group. If the participant is available, the first session will take place on the same day. The following sessions will be scheduled according to the medical diabetic foot consultations. In each session, two assessments of blood pressure and heart rate will be performed, before starting the session and at the end of the session. At the end of the fourth session, the T1 assessment will be performed, with a new administration of the questionnaires. Six months after T0, the T2 (follow-up) evaluation will take place, with the last administration of the questionnaires.
The interviews with patients, who completed the four sessions of relaxation, and with health professionals, will be conducted two weeks after T1, by a different researcher than the one involved in the intervention, to reduce the bias of social desirability.
