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Table 1 Properties of the outcome measures used to assess feasibility of the virtual decision lab

From: Launching a virtual decision lab: development and field-testing of a web-based patient decision support research platform

Measure Clinical contexts Format Scoring Psychometric properties
Decision aid acceptability [[1],[62]] Knee Osteoarthritis. 6 multiple choice items scored 1 “very/just right”, and 0 “somewhat/not at all” Adapted from the 10-item Ottawa Acceptability Scale. Available in English. 0-100 with higher scores indicating more acceptable. None reported.
Assesses patients’ subjective rating of the decision aid’s ease of use, clarity of information, length, level of detail provided, ability to hold one’s interest, and satisfaction with “how the website prepared you for discussing this decision with your doctor(s)” (Adapted from the 10-item Ottawa Acceptability Scale, O’Connor 1996).
Osteoarthritis decision quality index’s knowledge subscale [[1],[45]] Knee Osteoarthritis. 5 multiple-choice items scored 1 (correct) or 0 (incorrect). Available in English. 0-100, with higher scores indicating better comprehension. Retest reliability ICC = 0.83. Discriminates between patients and clinicians (p < 0.001) and patients who view decision aid and patients who had usual care (p < 0.001).
Assesses patients’ objective understanding of a) which treatment is most likely to relieve pain, b) rates of improved pain, c) rates of second replacement surgery, d) rates of complications, and e) months needed for recovery.
Preparation for decision making scale [[1],[46],[64]-[66]] Orthopaedics, prostate cancer, breast cancer, autologous blood donation, hormone replacement therapy. 10-item version, using 5-point Likert scale from 1 “not at all” to 5 “a great deal”. Available in English French, German, Italian. 0-100, with higher scores indicating better preparation. Alpha coefficients 0.92 to 0.96. Discriminates between people who do/do not find the decision aid helpful (p < 0.0001). Correlates with informed (r = −0.21, p < 0.01) and support (r = −0.13, p = 0.01) subscales of Decisional Conflict Scale.
Assesses patient’s perspective of how well an intervention prepared them to communicate with their physician about a decision. Includes identifying a decision, preferred role, values clarification, communication.
Decisional conflict scale [[1],[47],[66]] Osteoarthritis, disc herniation, spinal stenosis, prostate cancer, breast cancer, prenatal screening. 10-item low literacy version, using a 3-point Likert scale from 0 “yes” to 4 “no” Available in English, Spanish. 0-100, with scores below 25 associated with making a choice and scores above 37.5 associated with delaying decisions. For every unit increase, people are 59X more likely to change their mind, 23X more likely to delay decision, 5X more likely to express decisional regret, 3X more likely to fail knowledge test, and 19% more likely to blame doctor for any bad outcomes. Alpha coefficients >0.78. Discriminates between people who make and delay decisions; effect size ranges 0.4 to 0.8. Correlates to related constructs of knowledge, regret, and discontinuance.
Assesses patients’ perceptions of uncertainty about the options, modifiable factors contributing to uncertainty, and sense of effective decision making. Includes a Leaning Scale measuring strength of treatment preference and four subscales measuring uncertainty, informed, values clarification, and support.