Reading Statistics Items on TEAS, HESI, ASWB

By VeriScorePrep Team · 5 min

Statistics appears in TEAS math, HESI research, and ASWB research-evaluation items. A few concepts cover most items.

Key concepts to drill

• Mean, median, mode: average; middle; most common.
• Standard deviation: spread; ±1 SD covers ~68%, ±2 SD ~95% in normal distributions.
• Normal vs skewed distributions: normal is symmetric; right-skew has a long right tail (mean > median); left-skew has a long left tail (mean < median).
• p-value: probability of seeing the observed result (or more extreme) if there is no real effect. Convention: p < 0.05 = statistically significant.
• Confidence interval: range of plausible values for an estimate; wider = less certain.
• Odds ratio / relative risk / absolute risk reduction: how much more (or less) likely the outcome is in one group vs another.

Common items

• Given a data table, identify median.
• Given a distribution shape, identify skew direction.
• Given p-value vs alpha, interpret significance.
• Given confidence interval, conclude whether a null effect is plausible (yes if the interval includes the null value).

Pitfalls

• Confusing mean and median in skewed distributions (in income data, median is more representative).
• Treating small p-values as "proven" — they reduce uncertainty but don't prove.
• Confusing statistical significance with clinical or practical importance.

Practice

Drill a stats set; the same handful of concepts appears repeatedly and becomes fast.