Authors' reply: Letter to the Editor: Preference option randomized design (PORD) for comparative effectiveness research: Statistical power for testing comparative effect, preference effect, selection effect, intent-to-treat effect, and overall effect (SMMR, Vol. 28, Issue 2, 2019). (May 2019) - Heo, Moonseong; Meissner, Paul; Litwin, Alain H; McKee, M Diane; Karasz, Alison; Chambers, Earle C; Yeh, Ming-Chin; Wylie-Rosett, Judith