Application of standardized, techniques of data gathering permitted to obtain quantitative research results. However, a researcher cannot evaluate precisely the value of these results. He can only — but not always — assess ...

In the course of the survey on medical care utilization in Poland, abundant materials have been collected concerning the process of data gathering. The materials embrace: observation reports on interviews; personal data ...

The article is an introduction to the subsequent articles devoted to the investigations mentioned in the title. The investigations have not yet been terminated, and the ensuing conclusions are preliminary. The purpose of ...

Quite frequently a researcher is unable to evaluate the degree of truthfulness of the data obtained, while rare checking analyses show that some informations gathered in various researches are burdened with serious errors. A ...