Formulation of hypotheses

Definition

 * A Hypothesis'' is an assumption whose validity we must verify before proceeding with further scientific work.
 * Provisional theory is based on descriptive research/statistics, clinical observations, analytical studies, laboratory research, theoretical modeling.

Differential method

 * If the frequency of occurrence of a disease in two comparative populations (sets) is significantly different' and if it is possible to identify a factor that is present in one set and not in the other, then we can label this factor as  'cause of disease'.
 * Example: higher incidence of ca of the cervix in married women - and vice versa lower' incidence in nuns.

Match Method

 * If we can find a common factor in a number of different populations that are characterized by the occurrence of a disease, then this factor could be the 'cause of the disease.
 * Example: Semmelweis came to the conclusion that the cause of teenage fever was some kind of "dead poison" found 'on the hands of the attending obstetric staff.

Method of analogy

 * If there are ``certain similarities in the distribution of the observed disease with another disease for which we have more complete information, it would be possible to judge that both diseases have ``some common causes. We use a deductive way of thinking.

Companion Difference Method

 * The change in the frequency of the disease occurs in parallel with the change in intensity of the given factor.
 * Example: incidence of lung carcinoma increases with the number of cigarettes smoked'.

Links
ws:Formulace hypotéz

Related Articles

 * Methodology in epidemiology

References [ edit | edit source ]

 * 1) ↑ TIMMRECK, Thomas C..  An Introduction to Epidemiology. 3rd edition. Sudbury: John and Bartlett Publishers, 2002. pp. 205-210. ISBN 0763700606.
 * 2) ↑ BENCKO, Vladimir, et al. Epidemiology, teaching texts for students of the 1st Faculty of Medicine, Prague. 2nd edition. Prague: Charles University in Prague – Karolinum Publishing House, 2002. pp. 16-24. ISBN 80-246-0383-7.

References [ edit | edit source ]

 * TIMMRECK, Thomas C..  An Introduction to Epidemiology. 3rd edition. Sudbury: John and Bartlett Publishers, 2002. pp. 205-210. ISBN 0763700606.


 * BENCKO, Vladimír, et al. Epidemiology, teaching texts for students 1. LFUK, Prague. 2nd edition. Prague: Charles University in Prague – Karolinum Publishing House, 2002. pp. 16-24. ISBN 80-246-0383-7.