# The order of completing MDP and D12 does not affect the breathlessness responses: A randomised controlled trial

## TL;DR

This study found that the order in which two breathlessness questionnaires are completed does not significantly affect the results for people with cardiorespiratory disease.

## Contribution

The study demonstrates that questionnaire order does not significantly impact breathlessness scores in clinical settings.

## Key findings

- The mean difference in D12 total score between groups was −1.5, not reaching the minimal clinically important difference.
- Subdomain scores of MDP and D12 also showed mean differences below the minimal clinically important difference.
- The study lacked sufficient power to detect smaller but clinically significant differences.

## Abstract

Breathlessness is a common and distressing symptom across a wide range of medical conditions. Different aspects (dimensions) of breathlessness can be assessed using the Multidimensional Dyspnoea Profile (MDP) and Dyspnoea-12 (D12) questionnaires. We aimed to examine whether the order of completing MDP and D12 affects the breathlessness responses in people with cardiorespiratory disease.

This was a randomised controlled trial embedded within a longitudinal clinical study. Outpatients with cardiorespiratory disease were randomly assigned to either first complete the MDP or the D12. Primary outcome was mean difference in D12 total score between groups, secondary outcome was mean difference in D12 and MDP subdomain scores. Both outcomes were compared to the minimal clinically important difference (MCID) for each scale.

All 182 participants from the longitudinal study were included. 93 were randomized to complete MDP first and 89 to D12 first. Characteristics such as age, sex, main cause of breathlessness and smoking status were similar between groups. The mean difference for D12 total score (MCID = 2.8) was −1.5 (−4.2 to 1.3, p = 0.26) between groups. Mean differences between groups in subdomain scores were also below the corresponding MCID.

The order of completion of MDP and D12 did not impact the scores significantly, but the study lacked power to find smaller yet clinically significant differences. The study supports that the most practical order of completing the instruments can be used in future research and in clinical settings.