A novel 6-item screening questionnaire for Parkinsonism: validation and comparison between different instruments.
BACKGROUND
Several instruments have been developed to screen Parkinson's disease (PD); yet, there is no consensus on the items, number of questions, and diagnostic accuracy. We aimed to develop a new questionnaire combining the best items with highest validity to screen parkinsonism and to compare its diagnostic value with that of the previous instruments using the same database.


METHODS
157 patients with parkinsonism and 110 healthy controls completed a comprehensive screening questionnaire consisting of 25 items on different PD symptoms used in previous studies. To select the optimal items, clinical utility index (CUI) was calculated and those who met at least good negative utility (CUI ≥0.64) were selected. Receiver operating characteristics (ROC) curves analysis was used to compare the area under the curve (AUC) of different screening instruments.


RESULTS
Six items on 'stiffness & rigidity', 'tremor & shaking', 'troublesome buttoning', 'troublesome arm swing', 'feet stuck to floor' and 'slower daily activity' demonstrated good CUI. The new screening instrument had the largest AUC (0.977) compared to other instruments.


CONCLUSIONS
We selected a new set of six items to screen parkinsonism, which showed higher diagnostic values compared to the previously developed questionnaires. This screening instrument could be used in population-based PD surveys in poor-resource settings.
Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society (NVS), Karolinska Institutet, Stockholm, Sweden.
Seyed-Mohammad
SM
Fereshtehnejad
Mahdiyeh
M
Shafieesabet
Arash
A
Rahmani
Farzaneh
F
Farhadi
Hasti
H
Hadizadeh
Gholam Ali
GA
Shahidi
Ahmad
A
Delbari
Johan
J
Lökk
D000328:Adult; D000368:Aged; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D008875:Middle Aged; D020734:Parkinsonian Disorders / Q000175:diagnosis* / Q000453:epidemiology*; D012372:ROC Curve; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*