This study (2012) investigated the potential stress-reducing effects of exposure to real and artificial nature on patients in  a hospital room, and whether these effects could be explained by the perceived attractiveness of the room.

A hospital visit is often a stress-provoking experience characterized by fear, anxiety, stress, and uncertainty – these negative psychological feeling may have a deleterious effect on health and recovery. Environmental stimuli and exposure to nature in turn appear to have beneficial effects, thus aesthetic enhancements can provide unobtrusive methods for managing stress and anxiety and have positive impacts on health and well-being. Authors have suggested that people prefer natural elements because of their potential to provide restoration from stress.

Patients (457) were exposed to either real plants, posters of plants, or no nature (control) while waiting for their treatment. They filled in a questionnaire about their hospital experience and the experienced level of stress was measured with two scales and were combined in one index measuring experienced stress. At the end of the questionnaire, several patient characteristics were also measured, such as the type of their treatment and the number of their previous hospital visits.

The results showed, that

• Lower levels of stress were reported by both patients exposed to real plants and posters of plants (p = 0.04)
• These effects were partially mediated by the perceived attractiveness of the waiting room: they were rated as more attractive when elements of nature were present (p = 0.01)
• Other patient characteristics had no significant effects on the results

Researcher conclude, that natural elements in hospitals have the potential to reduce the patients’ feelings of stress and positively influence their well-being. This is a noninvasive and effective complementary therapy for patients.