Self-care behaviors among patients. A study in the Journal of Clinical Nursing (Vol. 29, 2020) examined the level of and identified factors affecting the self-care behaviors in patients with diabetic foot ulcers. A stepwise multiple regression analysis was used on 131 outpatients and inpatients with diabetic foot ulcers at two Korean hospitals, where the patients were asked to complete a survey questionnaire regarding self-care behaviors and expected related factors. A model of diabetes management 1y2 was built from the following variables: x1 = e 1 if male position 0 if female x2 = e 1 if without spouse 0 if with spouse x3 = e 1 if has diabetes education 0 if no diabetes education x4 = • 1 if have experience of hospitalization due to diabetes mellitus or its complications 0 if have no such experience x5 = e 1 if comorbidity 0 if no comorbidity x6 = Perceived stress (five–point Likert scale) x7 = Problem-focused coping style (four–point Likert scale) x8 = perceived family support (five–point Likert scale)

a. How many models are fit to the data in step 1? Give the general form of these models.

b. How many models are fit to the data in step 2? Give the general form of these models.

c. How many models are fit to the data in step 3? Give the general form of these models.

d. Explain how the procedure determines when to stop adding independent variables to the model.

e. Describe two major drawbacks to using the final stepwise model as the best model for diabetes management y.