We discussed the following Ch. 1 concepts data, statistics, population, census, sample, voluntary response sample (self-selected sample), correlation vs. causation, statistical significance, practical significance, misleading conclusions, reported results, small samples, loaded questions, order of questions, nonrepsonses, missing data, precise numbers, percentages, statistical thinking, parameters, quantitative vs. qualitative data, discrete vs. continuous functions, nominal vs. ordinal vs interval vs. ratio levels of measurement, observational study vs. experiments, lurking variables, random sampling, simple random sampling, systematic sampling, convenience, multistage sampling, stratified sampling, cluster sampling, cross-sectional vs. retrospective (case-control) vs. prospective (longitudinal or cohort) studies, randomization, replication, blinding, and placebos, confounding, sampling error, non sampling error, nonrandom sampling error.