Data Analysis
SECONDARY
Data for the primary outcome were analyzed using a 3-level linear mixed-effects modeling (LMM) approach [For the secondary outcomes, service uptake (iCBT referral and completion) and effort (hours) were modeled following the same approach as for the primary outcome, except that a 2-level LMM was applied as these measures were collected at the organization level only (ie, not at the level of staff members but only waves [Level 1] clustered at the organization level [Level 2]). For exploratory purposes, measures of exposure to the ItFits-toolkit (module-based log as an indication of use), CSQ, SUS, and perceived impact and helpfulness of the ItFits-toolkit were assessed descriptively as an indication of usability, satisfaction, impact, and helpfulness of the ItFits-toolkit from the perspective of implementers. Perceived impact and helpfulness were measured using a VAS, with a continuous scale ranging from 1.0 10.0. The scale scores for SUS and CSQ were calculated using the respective prescribed scoring systems. For CSQ, summed item rating scores were used [All observed data were included in the analyses following the intention-to-treat principle. We relied on the capability of linear mixed-effects models to estimate model parameters in case of missing values under the Missing at Random assumption [