In a study investigating the prevalence of vitamin D deficiency in the elderly, 1200 individuals with vitamin D deficiency were found among a group of 8000 Caucasians. Additionally, 800 individuals with vitamin D deficiency were identified among 3000 Asians. What is the overall prevalence of vitamin D deficiency in this elderly population?
A study investigated the effectiveness of a new statin therapy in preventing ischaemic heart disease in a diabetic population. Over a five-year period, 1000 patients were randomly assigned to receive the new therapy and 1000 were given a placebo. Among the placebo group, 150 patients experienced myocardial infarctions, while the group treated with the new statin had 100 infarctions. What is the percentage reduction in relative risk of MI provided by the statin therapy?
A study was conducted to evaluate the effectiveness of a new autoantibody test in detecting suspected Hashimoto’s disease in individuals over the age of 50 who reported fatigue. The test was administered to 1000 participants and compared to FNA biopsy results, which served as the gold standard for diagnosis. The table below displays the findings:
Antibody +ve Antibody -ve Total
Hashimoto’s disease confirmed at FNA 35 15 50
No evidence of disease at FNA 30 920 950
What is the approximate sensitivity of the autoantibody test for detecting Hashimoto’s disease in individuals over the age of 50 who experience fatigue?
To evaluate the effectiveness of a home cholesterol testing kit, a group of 500 individuals under the age of 40 were recruited. Each participant provided a blood sample for analysis. The results showed that 480 individuals had normal cholesterol levels and 20 individuals had high cholesterol levels. What is the sensitivity of the test?
In a primary prevention study of stroke comparing a new antihypertensive with conventional antihypertensive therapy, the number of patients who had a stroke over the study period was 200 in group 1 with the new therapy (n = 5200) versus 250 with conventional therapy (n = 4750).
What is the approximate odds ratio for the new therapy in preventing stroke among patients?
The mean cholesterol level in healthy men is 180 mg/dL and the standard deviation is 20 mg/dL.
What is the z score for a man with a cholesterol level of 200 mg/dL?
In a clinical trial of statin therapy for the secondary prevention of ischaemic heart disease, it was found that the therapy reduced cardiovascular mortality from 12% to 8% over a period of five years.
Assuming standard therapy as the baseline, what is the number of patients that need to be treated with statin therapy to prevent one death over five years?
What is the absolute risk reduction of stroke in elderly subjects treated with aspirin compared to those not treated, and how many elderly subjects would need to be treated with aspirin to prevent one stroke?
A study investigated the effectiveness of a new statin therapy in preventing ischaemic heart disease in a diabetic population aged 60 and above. Over a period of five years, 1000 patients were randomly assigned to receive the new therapy and 1000 were given a placebo. The results showed that there were 150 myocardial infarcts (MI) in the placebo group and 100 in the group treated with the new statin. What is the number needed to treat to prevent one MI during the study period?
A 35-year-old man is curious about maintaining a healthy diet. He currently weighs 106 Kg and stands at a height of 1.76 m.
To the nearest decimal point, what is his estimated body mass index (BMI)?