Combined Outcome Measure for Risk Communication and Treatment Decision-Making Effectiveness

Abstract

The Combined outcome measure for risk communication and treatment decision making effectiveness (COMRADE) is a 20-item patient questionnaire designed to evaluate key aspects of the clinical encounter. Specifically, it measures the patient’s level of patient satisfaction regarding communication quality with healthcare professionals (specialist, physician, or nurse), and the patient’s trust in the treatment decisions made during the care process. The foundational principle of the COMRADE scale is its focus on assessing the efficacy of involving the patient in therapeutic choices, thereby supporting the implementation of Shared Decision Making (SDM) practices.

Keywords

COMRADE, Risk Communication, Treatment Decision Making, Patient Trust, Shared Decision Making, Patient Experience, Communication Quality, Healthcare Outcomes.

Authors

Edwards A, et al. (2003), Koelewijn M (Dutch version)

Purpose

The primary purpose of the COMRADE instrument is to provide a standardized, patient-reported outcome measure for evaluating the success of clinical encounters that involve complex information exchange, particularly concerning medical risks and treatment options. It serves as a crucial tool for researchers and clinicians seeking to quantify how effectively healthcare providers communicate sensitive information and involve patients in critical decisions.

By focusing on both communication satisfaction and decisional confidence, COMRADE offers a holistic view of the patient experience. Its application is vital in settings where patient adherence and concordance with treatment plans are paramount, as these factors are often heavily influenced by the quality of interaction and the patient’s belief in the adopted course of action. This aligns directly with contemporary efforts to improve patient-centered care models.

Construct

The COMRADE scale operationalizes the effectiveness of the clinical decision-making process by measuring two distinct, yet related, psychological constructs. The first construct is Patient Satisfaction with Communication, which captures the clarity, empathy, and completeness of the information exchange regarding risks, benefits, and alternatives presented by the healthcare provider.

The second core construct is Patient Trust and Confidence in Decisions. This dimension assesses the patient’s subjective feeling of assurance and acceptance regarding the final treatment plan. This trust is theorized to stem directly from a successful communication process that facilitates Shared Decision Making, ensuring the patient feels informed, respected, and involved in their own care trajectory.

Validity

While specific psychometric details require reference to the original publication by Edwards et al. (2003), the validity of the COMRADE scale is typically established through rigorous testing. Content Validity is supported by the derivation of items directly related to established principles of effective risk communication and SDM frameworks. The 20 items are designed to cover the full spectrum of patient-provider interaction quality.

Construct Validity is assessed by examining how the scale scores relate to other measures of patient empowerment, health literacy, and health outcomes. It is expected that higher COMRADE scores correlate positively with measures of decisional quality and negatively with decisional conflict, thereby confirming that the instrument accurately measures the intended constructs of communication success and decisional confidence.

Reliability

Reliability testing ensures that the COMRADE instrument consistently measures the constructs over time and across different administrations. Internal Consistency Reliability, commonly measured using Cronbach’s alpha, is critical for a multi-item questionnaire like COMRADE. High coefficients (typically 0.70 or greater) are anticipated, indicating that the 20 items measure the same underlying dimensions (Communication and Trust).

Furthermore, Test-Retest Reliability is assessed by administering the scale to the same patient population at two different time points, assuming no significant clinical changes have occurred between assessments. Adequate test-retest correlations confirm the stability of the measure, ensuring that changes in scores reflect genuine changes in the patient’s perceived communication quality or decisional trust, rather than measurement error.

Factor Analysis

Exploratory and Confirmatory Factor Analysis (EFA/CFA) applied to the COMRADE scale typically confirms its underlying structure. Given that the scale measures two primary components—communication satisfaction and decisional trust—factor analysis is expected to reveal at least two distinct factors upon which the 20 items load differentially. This two-factor structure supports the theoretical framework that successful outcomes in treatment decision making require both effective information transfer and the subsequent development of patient trust.

The factor structure provides essential evidence for the scale’s structural validity, demonstrating that the scale is internally consistent with its conceptual design. Researchers utilizing the COMRADE instrument often analyze subscale scores based on these factor loadings to understand which specific aspect of the clinical encounter (communication process vs. decision outcome) most requires improvement.

Instrument

Test Type: Psychometric Questionnaire

Format: 20-item self-report questionnaire administered to the patient.

Language Available: English (Original), Dutch (Nederlandse versie by Koelewijn M)

Population Group: Clinical Patients

Age Group: Adults, Elderly

Population Details: Applicable to patients undergoing treatment decisions where complex risk information is exchanged with specialists, physicians, or nurses.

Test Methodology: Patient completion of a structured questionnaire, typically using a Likert-type response scale to gauge satisfaction and confidence levels.

Keywords

Patient-Reported Outcome Measure, Decisional Conflict, Healthcare Quality, Edwards A, Koelewijn M, Risk Communication, Patient Safety.

Authors

Author ORCID Identifier: N/A (Specific ORCIDs require external lookup of primary authors.)

Affiliation Email addresses: N/A (Contact details typically found in primary publication.)

Correspondence Address: N/A (Correspondence details typically found in primary publication: Edwards A, et al., 2003.)

Permissions & Fee and Test Year

The COMRADE scale was first published in 2003 by Edwards A, et al. Permissions for use, particularly for commercial or large-scale academic research, should be sought directly from the original authors or the publishing journal. Users should consult the original publication for specific details regarding licensing and authorized usage.

The original explanatory form (Toelichtingsformulier) for the Dutch version can be downloaded here: COMRADE Explanatory Form PDF.

The original measurement instrument (Meetinstrument) for the Dutch version can be downloaded here: COMRADE Measurement Instrument PDF.

Reference’s

• Edwards, A., Elwyn, G., Hood, K., Rollnick, S., & Russell, I. (2003). The development of COMRADE—a questionnaire to measure patient’s perception of involvement in decision making and communication satisfaction in consultations. Patient Education and Counseling, 50(1), 7-13.

• Koelewijn M. (Date of Dutch version publication not specified in source). Adaptation and validation of the Dutch version of the COMRADE questionnaire.

Items of the Combined outcome measure for risk communication and treatment decision making effectiveness

IMPORTANT: The following scale items must be preserved in their original language and must not be changed in any way.

The specific 20 items comprising the COMRADE scale were not provided in the source content. They are contained within the full measurement instrument document. Researchers interested in the exact phrasing and structure of the items should refer to the original publication by Edwards et al. (2003) or consult the Dutch measurement instrument PDF available here: COMRADE Measurement Instrument PDF.