The purpose of this study was to develop the "Itamikei", a small machine which records the subjective level of pain between 0-10. In addition to testing it's ease of operation and usefulness in the clinical practice environment. The "Itamikei" is 23 cm x 6 cm x 2 cm. It weighs 160 grams. It has 11 buttons, relating to the 0-10 Numeric Rating Scale (NRS). Each time a button is pushed the level of pain is recorded, along with the time and date. Later, this data can be transferred to computer displayed graphically showing the patient's subjective level of pain. This research was a case study for using the "Itamikei". One in-patient at the university hospital who had cancer pain was asked to use the "Itamikei" for 14 days. A graph was printed out and given to both the patient and the medical staff.
The results suggest the following:
1. Using the 0-10 NRS the patient could easily express her level of pain.
2. Because the "Itamikei" was easy to operate, the patient found no difficulty in entering her level of pain.
3. In graph form the daily transition in pain levels can be easily analyzed, and a program for managing pain can be prepare.

Objective: The Pain Level Memory Device (PLMD) is an instrument which patients can use to record their subjective level of pain. The usefulness of the PLMD on both medical staffs in managing cancer pain and the independence of patients were examined in this study. Method: Ten participants, inpatients at Nagoya University Hospital prescribed opioid drugs for cancer pain, were selected and asked to input any change in their pain level into the PLMD for a 14 day period between February and April 2005. A graph of the resulting data was printed and given to both the patient and medical staffs. And a questionnaire evaluating their experience with the PLMD was developed and administered to both. Relationships between the frequency of use of the PLMD and item-scores on the questionnaire were investigated. Results: The median number of inputs into the PLMD was 4.5 (range: 0.5-11) per day. High usage of the PLMD and each high score for the questionnaire items "The PLMD helped assessment of pain (p<.05)" and "The patients satisfaction with pain control improved (p<.05)" were strongly correlated. Spearman's rank correlation coefficient showed a relationship between the median number of inputs and the questionnaire items, "I used the PLMD whenever I intended to (r=.80, p<.01)", ""I saw graphs (r=.78, p<.01)", "I discussed graphs with my doctor (r=.70, p<.05)", "I felt that I participated in my pain management (r=.82, p<.01)", and "I would recommend the PLMD to other patients (r=.80, p<.01)". Conclusion: These results suggested that the PLMD could assist medical staff in the control of cancer pain and support the independence of patients.