Table 4 Success of feasibility study

Recruitment rate was ≥2 participants per month fitting the eligibility criteria

Recruitment rate was 1.36 eligible participants per month

No

The study recruited ≥70 % of all eligible potential participants

62.50 % of all eligible participants were recruited

No

Of the participants recruited to acupuncture group ≥90 % received their first acupuncture treatment within 1 week of recruitment

All participants received their first acupuncture treatment within 1 week of recruitment

Yes

After randomisation and allocation ≥90 % of participants received treatment as initially intended

All participants received treatment as intended and the study protocol was considered acceptable

Yes

Of the participants recruited to acupuncture group ≥80 % received all 8 acupuncture treatments

No participants received all 8 treatments (mean total number of treatments 5.14 (4.02–6.27))

No

Of the participants recruited to usual care group ≤10 % dropped out of the study

One participant (14.29 %) of participants dropped out of the usual care group

No

At the primary endpoint of the study outcome measures were completed by ≥90 % of participants

100 % of participants still enrolled on the study completed all outcome measures by the primary endpoint of the study

Yes

At 1 month after completion of the study, outcome measures were completed by ≥60 % of participants

Outcome measures were completed by 5 participants (33.33 %)

No

Qualitative data identified that outcome measures were acceptable and appropriate, that questionnaires and rating scales were easy to complete and that outcome measures could be identified for use in a definitive trial

Outcome measures were considered acceptable, appropriate and easy to complete. The HADS, PSS-10, EQ-5D-5 L, and ISI may not be appropriate for use in a definitive trial

Yes

Qualitative data implied that acupuncture was an acceptable and effective intervention for treating PLP with or without other secondary symptoms

Acupuncture/electroacupuncture was considered acceptable. Acupuncture was perceived to be effective at treating both PLP and other secondary complaints

Yes

Data were collected on the primary outcome measure (NRS) and effect size was calculated to inform a sample size calculation for a larger trial

Considering a 20 % dropout rate, 170 participants are recommended to be recruited to detect a significant change in a two-armed, parallel-group randomised controlled trial comparing usual care and acupuncture as measured using an 11-point NRS measuring average pain at 4 weeks

Yes

Qualitative and quantitative data implied that the acupuncture protocol used in the feasibility study was appropriate for use in a definitive multicentred randomised controlled trial

Participants did not drop out of the acupuncture group suggesting that it was acceptable. Participants’ symptoms generally improved over 6 treatments suggesting that 8 treatments was adequate. Acupuncture and electroacupuncture were considered acceptable, effective, and relaxing

Yes

The researcher was not aware which group participants had been enrolled to 100 % of the time

Blinding was not successful and the researcher knew through both participants and clinical staff at the amputee unit their group allocation

No