# SMHS Cronbachs

## Scientific Methods for Health Sciences - Instrument Performance Evaluation: Cronbach's α

### Under development

Include the following table in the Methods section!!!

 Subjects Items/Questions Part of the Assessment Instrument Total Score per Subject $Q_1$ $Q_2$ ... $Q_k$ $S_1$ $Y_{1,1}$ $Y_{1,2}$ … $Y_{1,k}$ $X_1=\sum_{j=1}^k{Y_{1,j}}$ $S_2$ $Y_{2,1}$ $Y_{2,2}$ … $Y_{2,k}$ $X_2=\sum_{j=1}^k{Y_{2,j}}$ ... ... ... ... ... ... $S_n$ $Y_{n,1}$ $Y_{n,2}$ … $Y_{n,k}$ $X_n=\sum_{j=1}^k{Y_{n,j}}$ Variance per Item $\sigma_{Y_{.,1}}^2=\frac{1}{n-1}\sum_{i=1}^n{(Y_{i,1}-\bar{Y}_{.,1})^2}$ $$\sigma_{Y_{.,2}}^2=\frac{1}{n-1}\sum_{i=1}^n{(Y_{i,2}-\bar{Y}_{.,2})^2}$$ … $$\sigma_{Y_{.,k}}^2=\frac{1}{n-1}\sum_{i=1}^n{(Y_{i,k}-\bar{Y}_{.,k})^2}$$ $$\sigma_X^2=\frac{1}{n-1}\sum_{i=1}^n{(X_i-\bar{X})^2}$$