Electrical Stimulation for the Treatment of Chronic Post-Stroke Shoulder Pain Using the Smartpatch System

A diary was used in the study to capture daily worst shoulder pain intensity over a 7-day period. The diary included a pain intensity question asked each day to the subject. The pain intensity question is excerpted from the Brief Pain Inventory - Short Form Question 3 (BPI-3) and is stated as "please rate your pain by circling the one number that best describes your pain at its worst in the last 24 hours". BPI-3 is a scale of 0 to 10 where 0 represents no pain and 10 represents worst pain. The median scores were calculated for each diary period. The median diary score at End of Treatment (EOT) was compared to the median baseline diary score to calculate the change in pain intensity. The group mean of the median scores for treatment was compared to the group mean of the medians scores for the control group at baseline and at EOT.

At each study visit following the baseline assessment, subjects were questioned if any changes in their medical status or condition had occurred. If the change was an adverse event, an adverse event form was completed by the site.

The degree to which shoulder pain interferes with daily activities was assessed using Question 9 of the Brief Pain Inventory (BPI-9) collected from the BPI Short Form administered during clinic visits. This question asks the subject to rate the degree to which their pain has interfered with general activity, mood, walking ability, normal work, relations with other people, sleep, and enjoyment of life on a scale of 0 to 10, where 0 is "does not interfere" and 10 is "completely interferes" within the last week. The mean of these seven scores will be calculated to obtain the pain interference score.

A diary was used in the study to capture daily worst shoulder pain intensity over a 7-day period. The diary included a pain intensity question asked each day to the subject. The pain intensity question is excerpted from the Brief Pain Inventory - Short Form Question 3 (BPI-3) and is stated as "please rate your pain by circling the one number that best describes your pain at its worst in the last 24 hours". BPI-3 is a scale of 0 to 10 where 0 represents no pain and 10 represents worst pain. The median scores were calculated for each diary period. The median diary score at 12 weeks post-treatment was compared to the median baseline diary score to calculate the change in pain intensity. The group mean of the median scores for 12 weeks post-treatment was compared to the group mean of the median scores for the control group at baseline.

The Medical Outcomes Study Short Form (SF-36v2) was administered at clinic visits to assess the impact of peripheral nerve stimulation on the subject's health-related quality of life. The SF-36v2 is a generic health survey designed to assess basic physical functioning and emotional well-being regardless of the disease or treatment. The 36 questions were grouped into two components: physical and mental. The survey was scored using norm-based scoring algorithm where a score of 0 indicates maximum disability and a score of 100 indicates no disability. Change in each component score was derived from End of Treatment score minus baseline score.

A diary was used in the study to capture daily average shoulder pain intensity over a 7-day period. The diary included a pain intensity question asked each day to the subject. The pain intensity question is excerpted from the Brief Pain Inventory - Short Form Question 5 (BPI-5) and is stated as "please rate your pain by circling the one number that best describes your pain on the average". BPI-5 is a scale of 0 to 10 where 0 represents no pain and 10 represents worst pain. The mean scores were calculated for each diary period. The mean diary score at End of Treatment (EOT) was compared to the mean baseline diary score to calculate the change in pain intensity.

The Patient Global Impression of Change (PGIC) scale was administered at EOT to assess subject perception of overall improvement and patient preferences. The PGIC scale asks subjects to rate their improvement with treatment on a 7-point scale (centered at 4) that ranges from "very much worse" to "very much improved" relative to baseline.

Subjects completed 7-day diaries, in which they listed all pain medications they took during the 7 days. A blinded third party medication committee reviewed medications collected for each 7-day diary period and scored medication changes, in comparison to the baseline diary medications as "no change" (no change in dosage or change is not clinically meaningful to impact pain outcomes), "increase" (clinically meaningful increase in medication that would impact pain outcomes), or "decrease" (clinically meaningful decrease in medication that would impact pain outcomes).

The Blinded Evaluator rated each subject enrolled at their site using a question adapted from the Clinical Global Impression (CGI) scale, known as the Clinical Global Impression-Improvement scale (CGI-I). For the CGI-I, a Blinded Evaluator was asked to rate the subject's total improvement compared to their condition at baseline. The CGI-I uses a 7-point scale (centered at 4) that ranges from "very much worse" to "very much improved".