Table 1.

Candidate THAPCA Efficacy Outcomes

A. Outcomes Assessing Change from Pre-Arrest to 12 Months
Outcome	Strengths	Weaknesses
i. Quasi-continuous change score (Death assigned lowest value, lowest possible VABS-II at one year next lowest value)	- Highest statistical power/ granularity - Adjusts for pre-arrest functional status	- Pre-arrest VABS-II possibly missing/inaccurate - Inappropriate to analyze as completely continuous - Results of statistical analysis difficult to interpret clinically, as magnitude of change - Magnitude and clinical significance of potential change vary according to baseline VABS-II
ii. Multicategorical, 5 levels:    Death    Lowest possible VABS    Worsening >30 points    Worsening 16–30 points    Worsening ≤15 points	- Improved power versus dichotomous outcome - Clinically meaningful categories - Adjusts for pre-arrest functional status	- Pre-arrest VABS-II possibly missing/inaccurate - Multiple cutpoints arguably subjective - Some categories not achievable for children with low pre-arrest VABS-II - Lowest possible VABS-II varies by age
iii. Dichotomous (Alive with worsening ≤30 points)	- Relatively interpretable and clinically meaningful “single” outcome - Adjusts for pre-arrest functional status	- Pre-arrest VABS-II possibly missing/inaccurate - Cutpoint arguably subjective - Less statistical power due to limited granularity - Children with baseline VABS-II < 30 points above minimum must be excluded

B. Outcomes Assessing 12-Month Status Only
Outcome	Strengths	Weaknesses
i. Quasi-continuous status (Death assigned lowest value, lowest possible VABS-II at one year next lowest value)	- High statistical power and granularity - Pre-arrest VABS-II not required	- Power loss with no baseline adjustment - Inappropriate to analyze as completely continuous - Results of statistical analysis difficult to interpret clinically, as magnitude of effect
ii. Multicategorical, 4 levels:    Death    VABS-II < 45 (includes minimally    conscious/vegetative)    VABS-II between 45–69    VABS-II ≥ 70	- Improved power vs. dichotomous outcome - Uses clinically meaningful categories - Pre-arrest VABS-II not required	- Power loss with no baseline adjustment - Multiple cutpoints arguably subjective
iii. Dichotomous (Alive with VABS-II ≥ 70)	- Most interpretable and clinically meaningful “single” outcome - Pre-arrest VABS-II not required for calculation	- Power loss with no baseline adjustment - Less statistical power due to dichotomization - Cutpoint arguably subjective - Children with baseline VABS-II < 70 must be excluded