The purpose of this study is to determine Clinically important difference and Response shift in quality of life in patients with Multiple Myeloma.

Multiple myeloma is a plasma cell tumor with an annual incidence of 6 pr. 100 000. In the absence of curative treatment, the aim of the therapy is not only to induce an objective response and a prolongation of survival but also to improve the patients quality of life.

This project will raise two problems which make QoL-data hard to interpret

1. In a clinical trial where many patients are included, statistically significant differences are obtained. However, there is widespread agreement that p-values do not indicate whether a particular finding has clinical significance because statistical significance does not necessarily equate to a meaningful difference or change in QoL. A crucial task for clinicians in interpreting trial-based QoL results is to determine if the observed change is clinically important to the patient.
2. When measuring changes in QoL in a pretest-posttest design,response shift can affect results. Patients with advanced disease can report surprisingly good QoL.Including response shift into quality of life research would allow a better understanding of changes in the QoL that patients report.

Inclusion Criteria:

• Multiple Myeloma
• Age > 18 years
• Informed consent

Exclusion Criteria:

• Terminal illness with life expectancy less than 3 months
• Unable to fill in a questionnaire in norwegian

Patients with Multiple Myeloma in all fases in the south and east of Norway