Table 2 Overview of outcome measures, corresponding instruments and measurement time points

 Decisional conflict

Decisional Conflict Scale (DCS) [46, 47]

16 items, 5-point Likert-type scale, score range: 0–100, higher scores indicate more decisional conflict.

Scores ≤25 are associated with follow-through decisions, and scores > 37.5 are associated with decision delay.

Cronbach’s alpha = > 0.78 [47, 48]

x

x

x

x

 Satisfaction with information

Three study-specific questions

How satisfied are you with the information about breast reconstruction? (5-point Likert-type scale: not at all – very satisfied), Did you miss information? (y/n), Would you have preferred less information? (y/n)

x

x

Subscale Satisfaction with Information of the BREAST-Q [49] (slightly adapted), for women with breast reconstruction only

Satisfaction with information (Reconstruction module): 15 items, 4-point Likert-type scale, very unsatisfied – very satisfied, score range: 0–100, higher scores indicating higher satisfaction.

Cronbach’s alpha = 0.94 [49]

 Satisfaction with plastic surgeon

Subscale Satisfaction with the Plastic Surgeon of the BREAST-Q [49]

Satisfaction with the Plastic Surgeon (Reconstruction module): 12 items, 4-point Likert-type scale, score range: 0–100, higher scores indicating higher satisfaction.

Cronbach’s alpha = 0.97 [49]

x

 Preparedness for decision making

Preparation for Decision Making Scale [50, 51]

10 items, 5-point Likert-type scale, score range: 0–100, higher scores indicate higher perceived level of preparation for decision making.

Cronbach’s alpha = 0.92–0.96 [51]

x

 Shared Decision Making

Shared Decision Making Questionnaire (SDM-Q-9) [52, 53]

9 items, 6-point Likert-type scale, score range: 0–100, higher scores indicate higher levels of perceived shared decision making.

Cronbach’s alpha = 0.88 [53]

x

 Patient involvement in decision making

Control Preferences Scale [54]

1 item, 5-point Likert-type scale

x

x

 Knowledge of breast reconstruction

Study-specific questionnaire, translated and adapted from a questionnaire used in prior research [55]

10 items that can be answered with true/false/I don’t know. Items are about contraindications, risk factors, duration of the recovery period, impact of breast reconstruction on sensation, number of surgical procedures, complexity of types of breast reconstruction, complications, impact of breast reconstruction on breast cancer treatment and survival rates and the opportunity to spare the nipple. Total score is the number of correctly answered items, ranging from 0 to 10.

x

x

x

x

 Decision regret

Decision Regret Scale (DRS) [56, 57]

5 items, 5-point Likert-type scale, score range: 0–100, higher scores indicating greater regret. Cronbach’s alpha = 0.81–0.92 [56]

x

x

 Choice regarding breast reconstruction

Patient-reported questions and data from EMR

x

x

 Satisfaction with breasts

Subscale Satisfaction with Breasts of the BREAST-Q

Subscale Satisfaction with Breast Outcome of the BREAST-Q [49] (women with breast reconstruction only)

Satisfaction with Breasts (Reconstruction or Mastectomy Module, as appropriate): 16 items (women with breast reconstruction)/4 items (women without breast reconstruction)).

Cronbach’s alpha = 0.96 (Reconstruction) [49].

Satisfaction with Breast Outcome (Reconstruction Module): 7 items, recall period: past 2 weeks. Higher scores indicate higher satisfaction.

Cronbach’s alpha = 0.88 [49]

x

x

 Body image

Subscale Body Image of the EORTC QLQ-BR23 [58]

4 items, 4-point Likert-type scale.

Cronbach’s alpha = 0.69–0.91 [58]

x

x

 Sexual functioning

Subscale Sexual Functioning of the EORTC QLQ-BR23 [58]

2 items + 1 item sexual enjoyment (if applicable), 4-point Likert-type scale.

Cronbach’s alpha =0.87–0.94 [58]

x

X

 Breast symptoms

Subscale Breast Symptoms of the EORTC QLQ-BR23 [58]

4 items, 4-point Likert-type scale.

Cronbach’s alpha =0.46–0.85 [58]

x

X

 Anxiety

STAI-6 (State scale of the State-Trait Anxiety Inventory) [59]

6 items, 4-point Likert-type scale,score range: 20–80, higher scores indicate higher levels of anxiety.

Cronbach’s alpha = 0.82 [59]

x

x

x

x

 Use of health care services

A selection of questions of the Medical Consumption Questionnaire (see https://www.imta.nl/), and data from EMR

Selection of questions on the number of consultations related to breast surgery with a (plastic) surgeon, nurse practitioner/ nurse specialist, social worker, psychologist, general practitioner and a physiotherapist, and the amount of received home care during the last 3 months (T2) or 9 months (T3).

x

x

 Health-Related Quality of life

EuroQoL-5D-5 L [60]

EuroQoL-5D-5 L descriptive system: 5 items, 5-point Likert-type scale, and the EQ Visual Analogue Scale: patients’ self-rated health.

x

x

x