Table 1.
Outcome measures summary schedule
| Initial assessment Clinic | Pre HRV-B phase (1 week) | HRV-B phase (4 weeks) | Post HRV-B phase (1 week) | |
| Autonomic screening (NLT) | √ | √ | ||
| Autonomic function (COMPASS 31) | √ | √ | ||
| Home autonomic test (aAP) | √ | √ | ||
| Fitbit wrist strap HRV, sleep data | √ | √ daily | √ | |
| Polar H10 chest strap HRV data | √ daily | |||
| LC-specific PROM C19-YRSm | √ | √ weekly | √ | |
| Daily function (WHODAS) | √ | √ | ||
| Quality of life (EQ5D-5L) | √ | √ |
aAP, adapted Autonomic Profile; COMPASS 31, Composite Autonomic Symptom Score; C19-YRSm, modified COVID-19 Yorkshire Rehabilitation Scale; EQ-5D-5L, EuroQol 5-Dimension 5-Level; HRV-B, heart rate variability biofeedback; LC, long COVID; NLT, NASA Lean Test; WHODAS, WHO Disability Assessment Schedule.