Table 1 Measurement instruments
Caregiver | ||||
Variable | Instrument/Source | No. of Items | Measurement | Type of Variable |
Self-rated mental health | Mental Component Summary (MCS) of the General Health Survey Questionnaire Short Form 12 (SF-12) [4, 33] | 6 | T0 – T1 | Primary outcome |
Self-rated physical health | Physical Component Summary (PCS) of the General Health Survey Questionnaire Short Form 12 (SF-12) [4, 33] | 6 | T0 – T1 | Secondary outcome |
Social support | Perceived Social Support Caregiving (PSSC) [35] | 9 | T0 – T1 | Secondary outcome |
Social conflict | Perceived Social Conflict Scale (SCS) [35] | 3 | Â | Control variable |
Caregiver reaction | 24 | T0 – T1 | Secondary outcome | |
Education level | Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) [46] | 2 | T0 | Control variable |
Demographic variables | Single items | 16 | T0 – T1 | Control variables |
Care Recipient | ||||
Variable | Instrument/Source | No. of Items | Measurement | Type of Variable |
Cognition | General Practitioner Assessment of Cognition (GPCOG) [42, 43] | 6 | T0 – T1 | Control variable |
Activities of daily Living | Functional Activities Questionnaire | 10 | T0 – T1 | Control variable |
Challenging behavior | Neuropsychiatric Inventory – Q [41] | 12 | T0 – T1 | Secondary outcome |
Demographic variables | Single items, e.g., age, gender, care dependency (care recipient) | 22 | T0 – T1 | Control variables |
Process Evaluation | ||||
Variable | Instrument (Source) | Measurement | Process Evaluation Domain | |
Recruitment strategies | Process documents of the TALKING TME study | T0 | Reach | |
Numbers of interested, refused, rejected, and included informal caregivers | Process documents of the TALKING TIME study Single items (T0) and process documents of the TALKING TIME study | Ongoing1 | ||
Randomization | Process documents of the TALKING TIME study | Ongoing | ||
Dropouts | Process documents of the TALKING TIME study | Ongoing | ||
Participant responsiveness | Single items, e.g., quality/satisfaction with the support group content, the group, and its process | T1 | Fidelity | |
Quality of delivery | Standardized support group protocols from the support group moderator and single items (T1), e.g., quality of the moderator, information booklet, telephone-based preliminary talk | Ongoing | ||
Adherence | Standardized support group protocols from the support group moderator and single items (T1), e.g., deviations from the intervention protocol, usage of the information booklet | Ongoing | Dosage | |
Dose | Standardized support group protocols from the support group moderator, e.g., participation of the informal caregivers in the support group calls | T1 | ||
Socio-demographic characteristics of the participants and care recipients | Single items, e.g., age, gender, care dependency (care recipient) | T0 – T1 | Context | |
Use of health care services | Use of service checklist [49] | T0 – T1 | ||