Comparing Cough Counting Methods in Hypertonic Challenges
Author Information
Author(s): Koskela Heikki O, Purokivi Minna K, Tukiainen Raija M
Primary Institution: Department of Respiratory Medicine, Kuopio University Hospital
Hypothesis
Is video recording of cough counting superior to simultaneous counting during hypertonic cough challenges?
Conclusion
Video counting is advisable for hypertonic histamine challenges but unnecessary for hypertonic saline challenges.
Supporting Evidence
- Video counting showed significantly higher cough counts during hypertonic histamine challenges.
- Simultaneous counting may miss coughs at high frequencies due to divided attention.
- The study included 1984 observation minutes for saline and 5373 for histamine challenges.
- Trained nurses counted coughs during challenges and from video recordings.
- Video recording allows for repeated viewing to ensure accurate cough counting.
- Simultaneous counting detected fewer coughs than video counting during high-frequency coughing.
- Video counting is considered the 'gold standard' for cough counting.
- Environmental factors can affect the accuracy of simultaneous cough counting.
Takeaway
This study looked at two ways to count coughs during tests. It found that using video is better when people cough a lot, but not needed when they cough less.
Methodology
The study analyzed cough counts from 82 saline challenges and 136 histamine challenges using both simultaneous and video counting methods.
Potential Biases
Potential bias due to the same nurse counting both methods without blinding.
Limitations
The individual counting coughs from video was not blinded to the simultaneous counts, which may introduce bias.
Participant Demographics
66 subjects, including healthy individuals and patients with chronic cough, with a mean age of 50 years.
Statistical Information
P-Value
0.23 for saline challenge, p < 0.001 for histamine challenge
Confidence Interval
95% limits of agreement for saline: -1.2 to 1.2 coughs/min; for histamine: -1.9 to 2.5 coughs/min
Statistical Significance
p < 0.001
Digital Object Identifier (DOI)
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