Researchers have developed a new tool for assessing dyspnea in patients with amyotrophic lateral sclerosis (ALS), called the 15-item Dyspnea-ALS-Score (DALS-15), according to results published in the Journal of Pain and Symptom Management.
The researchers developed a German language, disease-specific, patient-reported outcome measure for assessing dyspnea in patients with ALS. They used input from clinical experts and patients to create a preliminary 35-item questionnaire.
The questionnaire was completed by 94 participants with ALS and dyspnea. The researchers then performed Rasch analysis and tested for measurement issues including appropriate response categories, absence of differential item functioning, local independence, and unidimensionality.
Using Rasch analyses, the researchers came up with the final DALS-15. They found that the scale satisfies the Rasch Model with good fit statistics, absence of local dependency and differential item functioning, and acceptable unidimensionality.
In terms of test-retest reliability, the intraclass coefficient was 0.982 (95% CI, 0.964-0.991) and Lin’s concordance coefficient was ρc:0.981(95% CI, 0.963-0.991), which suggest good reproducibility.
The DALS-15 contains the following 15 patient-reported items, listed according to item severity:
- I have highly threatening dyspnea
- I am short of breath while sitting still
- I wake up because of breathlessness at night
- I have fear of suffocation
- Because of my breathing difficulty and its consequences, I feel isolated from other.
- My breathing is exhausting me.
- I feel restless.
- It depresses me when I have to stop activities because of my breathlessness.
- Breathlessness is a real problem for me.
- My breathing problems restrict my routine activities additionally.
- I feel short of breath.
- Due to shortness of breath, I avoid lying flat.
- I suffer from mild breathlessness.
- I have difficulties breathing during physical exertion.
- I have difficulties coughing up.
“The results of the current study suggest that the DALS-15 is able to fill an important gap in the assessment of patients with ALS,” the researchers wrote. “As long as ALS cannot be cured, evaluation and treatment of symptoms, in particular respiratory complaints is of fundamental importance, as symptomatic treatment with [non-invasive ventilation] has so far the greatest impact on survival and improves quality of life.”
Vogt S, Petri S, Dengler R, Heinze HJ, Vielhaber S. Dyspnea in amyotrophic lateral sclerosis (ALS): Rasch-based development and validation of a patient- reported outcome (DALS-15) [published online August 23, 2018]. J Pain Symptom Manage. doi:10.1016/j.jpainsymman.2018.08.009