Online Algorithm Identifies People at Risk of Parkinson’s Disease

Results Could Reflect Selection Bias

“Although only a small number of individuals have been independently diagnosed with Parkinson’s disease during follow-up so far, the overall incidence of 0.2% is consistent with the expected incidence rate in the age group of 60 to 80 from the general population (one to three per 1,000 per year) and supports the representativeness of our sample,” said Dr. Schrag.

The recruitment of participants may have introduced selection bias into the study, she acknowledged. “However, we did not use family history as an entry criterion, and the proportion with a positive family history was lower than in other landmark studies.” The fact that 17% of participants only completed the baseline assessment also may have introduced selection bias, “although there were no differences between those with or without follow-up, meaning that bias as a result of loss to follow-up was less likely.

“This Internet-based approach may be useful for population screening because it can easily be scaled upward,” added Dr. Schrag. “It will allow larger numbers of Parkinson’s disease cases that represent the spectrum of the disease to be identified, rather than what would be possible from cohorts of carriers of specific risk factors.”

—Erik Greb

Suggested Readings

Noyce AJ, R’Bibo L, Peress L, et al. PREDICT-PD: An online approach to prospectively identify risk indicators of Parkinson’s disease. Mov Disord. 2017 Jan 16 [Epub ahead of print].