Answer to Question 1
(a) The patient's problem must be chronic but stable so the effect of treatment over time can be seen.
(b) The treatment (usually a drug) should have a rapid effect and rapid cessation of effect when it is withdrawn so lingering effects don't persist in a placebo period.
(c) There have to be clear and objective goals that can be measured reliably. Different observers could draw different conclusions if criteria are too subjective
(d) The researcher needs to have a strategy for the analysis and interpretation of outcomes, again to avoid inappropriate conclusions.
Answer to Question 2
When researchers use multiple baseline studies, they measure different behaviors, sometimes at different starting points. When the different, but related behaviors all change similarly during treatment, it gives the researchers confidence that the treatment is effective; if treatment affected only one behavior, it could be that the single behavior was affected by some outside source.
Model for evidence-based clinical decision making.
Model of a nursing clinical decision support system
Examples of Medical Necessity Criteria
Criteria for Hospitalization for Feeding and Eating Disorders
Research Design in Clinical Psychology