Measuring the structure of visual fields in nursing units.

Objective: The purpose of this study was to develop quantitative measures of the structure of visual fields in nursing units.

Background: The structure of visual fields in nursing units-especially visibility toward patient beds-is believed to have a direct influence on the routine use of space by medical staff and patient outcomes within units. Although previous studies are suggestive, none has developed rigorous measures of the visibility within nursing units.

Methods: To compare the degree of visibility toward patient beds among different nursing units, the targeted visibility index (TVI) was introduced. The TVI measures the degree to which an observer can see all targets in a nursing unit. It provided a comparative spatial quality evaluation of various nursing unit configurations with differing numbers of patient beds. It was developed and programmed on the ArcGIS version 9.2 platform (ESRI Inc., Redlands, CA) with component object model-based ArcObjects and Visual Basic for Application language (Microsoft).

Results: The assessment of three nursing unit designs by TVI aligned exactly with empirical evaluations conducted in previous studies.

Conclusions: This study provided an opportunity and supplied relevant measures for healthcare facility designers to specify the visual structures of important behavioral effects. It is anticipated that the TVI will contribute to the understanding of healthcare design and the resulting outcomes.