Table 1 Study characteristics and quality of the nine eligible publications

[19]

Absolom K, et al. Qual Life Res. 2015.

NIHR

Y

(PPI group member)

Y

(PPI group member)

N

N

Poor/fair quality

Oncology

UK

Springer Nature

[20]

Pollard K, et al. Int J Health Care Qual Assur. 2015.

Higher Education Innovation Fund, West of England University

N

Y

(service user research partners)

N

N

Poor/fair quality

General

UK

Emerald

[21]

Hyde C, et al. Health Expect. 2017.

NIHR

N

Y

(patient research user group members)

N

N

Good quality

Pain

UK

Wiley

[22]

Mann C, et al. Res Involv Engagem. 2018.

NIHR Health Services and Delivery Research Programme

Y

(Patient Involvement in Primary Care Research group)

Y

(Patient Involvement in Primary Care Research group)

N

N

Good quality

Chronic multiple morbidities

UK

BMC

Springer Nature

[23]

Pérez Jolles MP, et al. Health Expect. 2017.

PCORI

Y

(mentor parent group members)

Y

(mentor parent group members)

N

N

Good quality

Mental health

US

Wiley

[24]

Howe A, et al. Res Involv Engagem. 2017.

NIHR Health Services and Delivery Research Programme

Y

(PPI representatives)

Y

(PPI representatives)

N

N

Good quality

General

UK

BMC

Springer Nature

[25]

Forsythe L, et al. Qual Life Res. 2018.

PCORI

Y

(patient advisor)

Y

(patients, caregivers, advocacy groups)

N

N

Good quality

General

US

Springer Nature

[26]

Blackburn S, et al. Res Involv Engagem. 2018.

NIHR School for Primary Care Research

Y

(PPI contributors)

Y

(PPI contributors)

N

N

Good quality

General

Primary care

UK

BMC

Springer Nature

[27]

Barnfield S, et al. Res Involv Engagem. 2017.

Medical Research Council, UK

N

N

N

N

Fair quality

Stroke

UK

BMC

Springer Nature