Inferential statistics
REGRESSION, MRS
Inferential statistical analysis was a two-factor design repeated for intention to treat (ITT), complete case (CC) and per protocol (PP) analysis. ITT; all participants included with last outcome carried forward for missing data (LOCF). CC; participants who responded to the follow-up survey and PP; participants who received allocated intervention and responded to the follow-up survey. The level of significance was set to 0.05. The IBM SPSS Windows version 25 and 27 was used for statistical analyses.For the effect of either intervention at 6- and 12-month follow-up linear and ordinal regression were used. The first linear regression was performed with mean change in SF-36, HADS, s-ED, PSS-14, MADRS-S and MRS as the dependent variable. The mean changes were not normally distributed, so they were transformed using Blom’s rank-based method [Finally, a summary of the results from linear and ordinal regression analyses were presented in a summary table. In the summary table a desired effect of any of the two interventions was denoted with a + sign if it was statistically significant in at least one of ITT, CC and PP. A double + sign indicates a desired effect of intervention seen in two of the three statistical analysis and three + signs indicate a statistically significant effect in all three analysis. In analogue with this 1–3 minus signs indicate a statistically significantly undesired effect of the intervention. The odds ratio is also presented for any statistically significant effect seen in the ordinal regression of the ITT analysis. It should be noted that some questionnaires estimate health while others estimate symptoms. Hence, a desired effect in some outcome variables result in an odds ratio > 1 while in others an odds ratio < 1. To enhance understanding this was transformed in the summary table, so a desired effect always had an odds ratio > 1 while an undesired effect always had an odds ratio < 1.