Matched Case Control Study
Question 1: These data show a list of 9 patients. Two of
the patients have received an experimental treatment. Identify which of the
patients in the following table could serve as controls for the two cases.
Select the possible controls randomly using the lowest random number. Match on
age. Show a Kaplan Meier survival
curve. For each month, show the percent of cases or controls that have
not fallen since the start of the study.
Question 2: Establish the percent of days the following patient is in therapeutic range. On days when blood pressure was not measured, assume that blood pressure is the same as the nearest data point less than 7 days away. For all other days assume that the blood pressure is unknown. Solution►
Question 3: Hypertension is a pervasive medical condition in the U.S. that can often be managed through diet. A study was performed to examine the impact of diet in controlling hypertension by reducing sodium intake. A control group was given a diet rich in fruits and vegetables, while a randomly selected study group was given a diet that also included low-fat dairy products. Both groups initially participated in a 3-week period in which they consumed a ‘typical’ American diet. During this period the baseline data for sodium intake were obtained (see Table below). This is a type of statistical problem that you might face in a course in health systems research. Answer►
Question 4: Venous thromboembolism (VTE) is a medical condition in which blood clots form within a vein that can block the vein or break off and become a life-threatening pulmonary embolism. One treatment for VTE is the use of anticoagulants such as warfarin. Anticoagulants are effective, but their level in the patient’s blood must be actively monitored. If it is too high, the patient is at risk for internal bleeding; too low and anticoagulant won’t have a therapeutic effect. Dosing for anticoagulants is monitored using INR, a measure that represents the ease with which blood clots. The target INR for effective treatment of VTE is between 2.0 and 3.0. Clinical protocols suggest that patients with a transient risk for VTE be put on warfarin for a three-month period. During this time the INR is monitored weekly. Table below represents the experience of a typical patient. This is a type of statistical problem that you might face in a pharmacy course. Answer►
Prepared by Farrokh Alemi, Ph.D. Most recent revision 06/01/2017. This page is part of the course on Statistical Process Improvement in EHR.