Clinical Trials

❘❙❚■ Indexpopulation, 186, 187sample, 186, 187significance threshold, subgroup analysis, 269simple randomization, 67–68, 68single-blinded studies, 77–78single-center clinical trials, definition, 3–4sources of erroneous results, 5spaghetti plots, 420, 421standard deviation, definition, 173standard distribution, t-test distributions vs, 201standard error, definition, 456statistics, 165–252cluster randomized trials, 146confidence intervals see confidence intervalsdata types see dataglossary, 452–456meta-analysis, 444, 445–449proportion comparison see proportions,comparison ofprotocol development, 32significance tests see significance testsvariables see variablessee also repeated measurementssteering committee, protocol development, 35stem and leaf plots, 413–414, 415, 423‘stopping for efficacy,’ definition, 10‘stopping for safety,’ definition, 10stratification, confounding, 302stratified analysis, 6, 292stratified randomization method, 6, 70–71, 71, 300study management bias, 58–59pharmacokinetic profiles, 58, 59study selection, meta-analysis, 442–443study timetable, protocol development, 33subgroup analyses, 265–272data review, 270definition, 266example, 266, 268, 270interaction testing, 269limitations, 267, 267–269patient imbalance, 268–269solutions, 269–270type I error, 268multiplicity, 333, 337planning, 270post hoc analysis, 269–270selection, 266–267significance threshold adjustment, 269uses, 267superiority study, 4definition, 114surrogate endpoints see endpointssurvival analysis, definition, 456survival dataanalysis see belowdata types, 170survival data, analysis, 235–252basic concepts, 236–238censoring, 236, 237hazard function, 238survival function, 238example, 236see also Candesartan in Heart failure –Assessment of Reduction in Mortalityand morbidity (CHARM); pancreaticcancer trialproportional hazards model, 245–248assumptions, 245–247, 246description, 245results interpretation, 247–248, 248survival curves, 239–242Kaplan–Meier methodsee Kaplan-Meier plotlog-rank test see log-rank testtwo-arm trial, 249–250survivor function, definition, 279systematic bias, critical appraisal of reports,431–432TT 1/2, bioequivalence trials, 123–124, 124tables, 391–405adjustments, 402analysis methods, 402asterisks, 404blank cells, 404complex, 394–396confidence intervals, 403construction, 400–404descriptive statistics, 403explanatory information, 401figure combinations, 394–396figures vs, 397–398follow up, 401footnotes, 402heading, 401information present, 400instead of text, 396–397478