Research Interpretation - National Physical Therapy Examination NPTE

1. State the formula for absolute risk reduction (ARR) using event rates.

   $ARR = CER - EER$. Calculates the absolute difference in event probabilities between control and experimental groups.

2. What is the usual meaning of statistical significance at $\alpha = 0.05$?

   Reject $H_0$ when $p < 0.05$. Indicates evidence strong enough to reject the null hypothesis at the 5% significance level.

3. What does minimal clinically important difference (MCID) represent?

   Smallest change perceived as beneficial and clinically meaningful. Represents the threshold for change that is meaningful to patients or clinicians beyond statistical significance.

4. State the formula for minimal detectable change at $95\%$ confidence, $MDC_{95}$.

   $MDC_{95} = 1.96\,SEM\sqrt{2}$. Calculates the change threshold exceeding measurement error at 95% confidence using SEM.

5. What is statistical power expressed as a formula?

   $1 - \beta$. Represents the probability of correctly detecting a true effect by rejecting a false null hypothesis.

6. What is the definition of reliability in measurement?

   Consistency or reproducibility of scores across repeated measures. Refers to the stability and consistency of measurements when repeated under similar conditions.

7. What does effect size (standardized) primarily quantify?

   Magnitude of difference independent of sample size. Standardizes the effect magnitude to enable comparisons across studies regardless of sample size variations.

8. What does a $p$ value represent in hypothesis testing?

   Probability of results as extreme as observed if $H_0$ is true. It quantifies the likelihood of obtaining the observed data or more extreme under the assumption that the null hypothesis holds.

9. Which option best indicates a result is statistically significant using a CI for a mean difference?

   The $95\%$ CI does not include $0$. Signifies statistical significance for differences when zero falls outside the interval, implying a non-zero effect.

10. Which reliability statistic is most appropriate for continuous data with raters or sessions?

    Intraclass correlation coefficient (ICC). Suitable for assessing reliability in continuous measures involving multiple raters or repeated trials.

11. What is a Type I error in hypothesis testing?

    Rejecting a true $H_0$ (false positive); probability $= \alpha$. Occurs when the null hypothesis is incorrectly rejected despite being true, with risk controlled by the alpha level.

12. What is a Type II error in hypothesis testing?

    Failing to reject a false $H_0$ (false negative); probability $= \beta$. Happens when a false null hypothesis is not rejected, missing a true effect, with probability denoted as beta.

13. State the formula for number needed to treat (NNT) from ARR.

    $NNT = \frac{1}{ARR}$. Determines the number of patients requiring treatment to avert one adverse outcome based on risk reduction.

14. What is the correct interpretation when $p > 0.05$?

    Fail to reject $H_0$; insufficient evidence of a difference. Suggests lack of sufficient evidence to claim a difference, without proving the null hypothesis true.

15. Which reliability statistic is most appropriate for categorical agreement (beyond chance)?

    Cohen's $\kappa$. Measures inter-rater agreement for nominal data while accounting for chance-expected concordance.

16. Identify what it means if a patient's change score exceeds $MDC_{95}$.

    Change likely exceeds measurement error (real change). Indicates the observed change is probably genuine and not attributable to random error.

17. Identify the correct conclusion if a $95\%$ CI for a mean difference includes $0$.

    Not statistically significant at $\alpha = 0.05$. Means zero is a plausible value for the difference, indicating no evidence against the null at 5% level.

18. Which option best indicates a result is statistically significant using a CI for a ratio (RR or OR)?

    The $95\%$ CI does not include $1$. Indicates significance for ratios when 1 is excluded from the interval, suggesting deviation from no effect.

19. What does a $95\%$ confidence interval (CI) mean in repeated sampling?

    About $95\%$ of such CIs would contain the true parameter. Reflects that in hypothetical repeated sampling, 95% of intervals would capture the true population parameter.

20. State the formula for the standard error of measurement (SEM).

    $SEM = SD\sqrt{1-ICC}$. Estimates absolute measurement error using standard deviation and reliability coefficient.

21. What does a higher ICC value indicate about measurement reliability?

    Greater relative reliability (better ability to distinguish individuals). Reflects improved capacity to differentiate between individuals relative to measurement error.

22. What is the definition of validity in measurement?

    Degree to which an instrument measures the intended construct. Ensures the tool accurately assesses the targeted attribute or concept it is designed for.

23. State the formula for Cohen's $d$ for two independent means.

    $d = \frac{\bar{x}_1 - \bar{x}_2}{SD_{pooled}}$. Standardizes the difference between means by dividing by the pooled standard deviation for comparability.

Study these flashcards