Читать книгу Statistics in Nutrition and Dietetics - Michael Nelson - Страница 38

The underlying purpose of most research is to find evidence in support of causality of the type: ‘If A, then B’. Of course, we may just be interested in describing what is going on in physiological systems (what dietary factors are associated with low serum total cholesterol levels?) or in the population (are women aged 75 years and older at greater risk of osteoporosis‐related fracture of the hip if they have low levels of physical activity?) More often, we want to know if there is a causal relationship between these factors (does an increased level of physical activity protect against osteoporosis‐related hip fracture in women aged 75 and older?). Public health recommendations to improve nutrition and nutrition‐related outcomes need strong evidence of causality before they can be promoted to the general public. Confusion in the mind of the public is often caused by the media promoting a ‘miracle cure’ based on a single study (it makes good press but bad science). Food manufactures are often guilty of using weak evidence of causality or vague terms about ‘healthiness’ to promote sales of their products.¹⁰