3.1. Baseline characteristics of participants and trial structure
Sixtyresidentsandmedicalstudentswereinvitedtoparticipate,and
fifty-nine agreed. Three were excluded due to travel outside the south-
ern Brazilian region in the last 120 days. Four did not come for the first
appointment, so were excluded before any intervention (Fig. 1). Base-
linecharacteristicsare shown in Table1.Beforecholecalciferol adminis-
tration,serum25OHDlevelswerebelow30ng/mLinall55participants,
of which 36 had serum 25OHD levels between 10 and 20 ng/mL, and in
6 it was below 10 ng/mL. PTH levels ranged from 10.2 to 61.5 pg/mL,
and one participant had low serum total calcium and high normal
range serum PTH levels, respectively, 8.3 mg/dL (8.8–10.2 mg/dL), and
61.5 pg/mL (10.0–65.0 pg/mL). Serum albumin levels were in the
normal range in all. No participant smoked. Six female participants
were taking oral contraceptives in the ezetimibe group and seven in
the placebo group.
3.2. Follow-up
Only one participant in the placebo group forgot to take a capsule.
One participant in the placebo group threw up one hour after taking
the cholecalciferol capsule and was excluded from the analyses. Two
participants in the ezetimibe group reported headache. The incidence
of diarrhea was equal in both groups. No other adverse drug reactions
were reported.