Massage therapy for symptom control: outcome study at a major cancer center

This study surveyed 1,290 patients seen over a three-year period at Memorial Sloan-Kettering Hospital, asking them to rate symptoms such as pain, nausea, stress/anxiety, fatigue and depression on a 0 to 10 visual analog scale (YAS) before and after massage. VASs measure the intensity or magnitude of sensations and subjective feelings, and the relative strength of attitudes and opinions about specific stimuli. They are often used in health care research. The majority of the 329 outpatients received hour-long massages consisting of Swedish (75 percent), with far fewer receiving foot massage (13 percent) and light touch (6 percent), while the 961 inpatients— who tended to be sicker and more medically fragile—received shorter massages lasting for 20 minutes. Inpatients were more likely to have foot massage (56 percent), Swedish massage (33 percent) and light touch (7 percent). Swedish massage and light touch were slightly more effective (58 percent improvement in symptoms) compared to foot massage (50 percent improvement). The before and after scores were analyzed taking the initial or baseline score into account, using a method called analysis of covari-ance, or ANCOVA for short- The most striking finding was the approximately 50 percent reduction in symptom scores, even for patients who reported high scores initially. Outpatients showed 10 percent greater improvement compared to inpatients.

One explanation for this difference is that outpatients may have been less ill to begin with compared to inpatients. Outpatients also received a bigger “dose” of massage, 60 minutes compared to 20 minutes. This also may explain the longer duration of the symptom relief observed in outpatients. A representative subset of each group was followed for different periods of time after the massage. For inpatients, symptom severity began to increase again within two to five hours after the massage treatment, while symptom scores for outpatients did not return to baseline within 48 hours.

This was a landmark study because it had one of the largest sample sizes to date for evaluating massage. A criticism often made of earlier studies on massage is that they had small sample sizes or too few participants. The problem with having too small a sample is that there is insufficient statistical power to determine whether a result is truly the effect of the treatment being evaluated or is just the effect of chance—the researchers may fail to detect a genuine effect because there are not enough people in the study. As a rough guide, look for at least 10 participants per group for every outcome being measured.
At the same time, there is a limitation to this study. The design of the study is an observational one, comparing patients’ symptoms before massage and after massage. There was no control group, so we don’t know if patients’ symptoms might have decreased regardless of receiving massage, or whether a different treatment might have been more or less effective. In terms of demonstrating a link between cause (massage) and effect (symptom reduction), the most that we can say is that massage is associated with a reduction in symptoms in these cancer patients. It would be overreaching to say that this study, as large and well-done as it is, “proves” that massage is an effective treatment for reducing these symptoms in people with cancer. This is why, when discussing research findings, we say that the study suggests or demonstrates an association between two events, rather than proving a cause and effect relationship.