The team from Case Western Reserve University, Cleveland, Ohio, USA and the Buddhist Tzu-Chi General Hospital in Taiwan, looked at the impact of music on sleep.

They monitored the sleeping patterns of 60 Taiwanese people with sleep problems aged 60-83, after randomly assigning half to listen to 45 minutes of soft music at bedtime. During the next three weeks, the participants in the music group experienced a 35 per cent improvement in overall sleep quality compared with the control group.

They also showed significantly better scores in five of the six subcategories used to measure sleep quality. These included better and longer night time sleep and fewer related problems during the day.

Researchers Dr Hui-Ling Lai and Professor Marion Good report that the music group experienced physical changes which encouraged restful sleep, including lower heart and respiratory rates.

Dr Lai writes: "The difference between the music group and the control group was clinically significant. The music group reported a 26 per cent overall improvement in the first week and this figure continued to rise as they mastered the technique of relaxing to the sedative music.

"Music is pleasant and safe and the technique we used in our study is quick and easy to learn is low cost, and could be used readily by nurses. It is easy to use and does not cause side effects," she added.

The research is published in the February edition of The Journal of Advanced Nursing. It builds on Professor Good?s previous finding that music and relaxation can help reduce post-operative pain.