Hovedundersøgelse

Hovedundersøgelse is a term used in Danish research methodology to denote the main data collection phase of a study. It is the central investigation designed to answer the primary research questions and to estimate the main endpoints with sufficient precision. In many projects it follows preliminary work such as forundersøgelser (pilot studies or feasibility assessments) and may be complemented by follow-up or ancillary studies.

Planning and design of a hovedundersøgelse involve a clearly defined target population, a sampling strategy, and a sample size determined by power calculations. The study uses standardized measurement instruments and procedures, with training for data collectors and procedures for quality control. A pre-specified analysis plan guides the handling of data, missing values, and statistical methods to ensure validity and reliability of the findings.

The outputs of a hovedundersøgelse are intended to be generalizable to the wider population of interest and often focus on primary endpoints, while also collecting secondary measures. Results support inferential conclusions, inform policy or practice, and contribute to scientific knowledge through publications and reports. The phase is typically designed to stand on its own but may be integrated with other study components, such as longitudinal follow-up or contextual sub-studies.

Ethics and governance are integral, including approvals from relevant ethics committees, informed consent from participants, data protection considerations, and transparency in reporting. The concept is widely used across epidemiology, clinical research, and social sciences in Denmark to structure robust, objective data collection and analysis.