[Evaluation of subjective happiness in the elderly using a visual analogue scale of happiness in correlation with depression scale].

A Visual analogue scale of happiness (VAS-H) was applied to elderly population in a community to evaluate their subjective quality of life. The study population consisted of 313 elderly people aged over 75. Using a 20 cm visual analogue scale (VAS), VAS-H was measured by asking subjects to place a single vertical mark on a horizontal line at a point corresponding to their current subjective degree of happiness judged from health condition and psycho-social background as a whole; The VAS-H was anchored on the left and with the words "-100%; unhappiest" and on the right end with the words "+100%; happiest". The scores of VAS-H (%) were obtained by multiplying the distance (cm) from the zero point to the vertical line by 10. To determine the characteristics of VAS from the standpoint of the quality of life, we compared VAS with scores of two kinds of established depression scale, because the mood which was assessed by these scale was supposed to be an important factor of the quality of life. The results of the simultaneously assessed Geriatric Depression Scale (GDS), and Zung's depression scale (SDS) which was obtained 1 year before for the same subjects were compared with that of VAS-H. The score of VAS-H had a significantly negative correlation with both GDS and SDS. In conclusion, VAS-H was a simple and useful method to evaluate degree of subjective happiness which was one factor of quality of life in the elderly people.