TABLE 4.

Practice effect-adjustment and reversion rates.

	Reverters M MCI	Reverters S MCI	Reversion in specific domain
			Memory	Attention/EF	Language
Count
Unadjusted	30	73	66	28	31
Adjusted	26	53	44	26	29
Difference	−4	−20	−22	−2	−2
χ2; p-value	2.25 p = 0.13	18.1 p < 0.001	20.0 p < 0.001	0.5 p = 0.48	0.5 p = 0.48
Reversion rate
Unadjusted	40.5%	28.7%	24.7%	36.3%	44.3%
Adjusted	35.1%	20.9%	16.5%	33.8%	41.4%
Difference	−5.4%	−7.8%	−8.2%	2.6%	2.9%
% change in reversion	Δ13.3%	Δ27.4%	Δ33.3%	Δ7.1%	Δ6.5%

The “Count” section displays the number of participants who reverted from a classification or impairment based on practice effect-unadjusted and -adjusted data. Those who reverted from multi-domain mild cognitive impairment (M MCI) at baseline to either single domain MCI (S MCI) or cognitively normal are displayed in the “Reverters M MCI” column. Those who were classified as S MCI at baseline and reverted to cognitively normal at follow-up are listed in the “Reverters S MCI” column. The “Reversion in Specific Domain” section refers to individuals who had a baseline impairment in a domain (memory, attention/executive functioning, or language) but not at follow-up; participants in these columns may be impaired in other domains at either baseline or follow-up. The Difference row displays how many fewer participants reverted when adjusting for practice effects (i.e., Adjusted count – Unadjusted count). McNemar χ² tests were used to evaluate the impact of practice-effect adjustment on classification or impairment reversion; p-values are presented.

The “Reversion Rate’ section lists the reversion percent for each column by dividing the counts provided above by the baseline prevalence of each classification shown in Table 1. For example, 74 people were classified as M MCI at baseline and 30 reverted at follow-up when using unadjusted data. Therefore, the reversion rate for the unadjusted M MCI reverters was 30/74. The difference row subtracts the reversion rate using Unadjusted data from the rate using Adjusted data. The “% change in reversion” row shows the percent change in reversion rate by dividing the difference by the unadjusted reversion rate: e.g., Δ13.3 = 5.4/40.5.