Short Answer

 
Look at “Changes in Medical Errors after Implementation of a Handoff Program” and answer the following questions:

Was this study descriptive, relational, or causal?
Was it cross-sectional or longitudinal?
Was it qualitative or quantitative?
What was the hypothesis? Was it one-tailed or two tailed?
What was the unit of analysis?
What was at least one independent variable? 
What was at least one dependent variable? 
In the “Study Outcomes” section, a measurement is described as follows: “Two physician investigators classified each suspected incident as an adverse event, a near miss or error with little potential for harm, or an exclusion.” What study constructdoes this measure? Is this level of measurement nominal, ordinal, interval, or ratio?
Make a statement of ecological fallacy pertaining to the conclusion of this study.
Was any relationship found between independent and dependent variables? Was the relationship causal? 
In the fourth from the last paragraph (starting with “although the implementation…”) a study limitation is discussed. What type of validity is threatened here–Conclusion, Internal, Construct, or External? Why?
In the next paragraph (starting with “our intervention…”) another study limitation is discussed. What type of validity is threatened here–Conclusion, Internal, Construct, or External? Why?