Table 1 Eligibility criteria using the SPIDER framework

Sample (S)

Papers including patients with severe or very severe COPD aged 18 years or older in need of PC, including advanced, late-stage, and end-stage COPD and do-not-resuscitate or comfort-measures-only orders. Patients with severe or very severe COPD using NIV treatment are defined as patients with PC needs

Papers including relatives of COPD patients in need of PC

Papers including HCPs caring for COPD patients with PC needs

Studies will be included regardless of reasons for or length of NIV treatment

Papers including patients younger than 18 years and patients that have mild and moderate COPD

Papers including relatives of patients with mild or moderate COPD

Papers including HCPs caring for patients with mild to moderate COPD

Papers including patients without a COPD diagnosis

Phenomenon of Interest (PI)

Studies related to NIV treatment, including mask, intermittent positive-pressure ventilation, bilevel positive airway pressure, and continuous positive airway pressure, in all healthcare settings and in all phases of the PC trajectory. Studies will be included if the COPD patients have been treated with NIV in PC, regardless of the reasons for or length of NIV treatment

Use of NIV to prolong life and/or for alleviation and comfort

Use of NIV with a curative intention

Studies exploring other respiratory interventions or treatment exercises and studies focusing on other palliative measures

Studies including diseases other than COPD

Design (D)

Studies with qualitative, quantitative, or mixed-methods designs

Evaluation (E)

Perspectives and experiences of COPD patients, relatives, and HCPs regarding NIV to patients with COPD with PC needs

Studies exploring the experiences and perspectives of students

Studies investigating patients’, relatives’, or HCPs’ experiences of specific interventions or treatments

Research Type (R)

All research types of peer-reviewed studies published in scientific journals in German, Spanish, Swedish, Danish, Norwegian, or English

Case studies, case–control studies, reviews of any type, clinical guidelines, and master’s and PhD theses

Grey literature, such as conference proceedings and abstracts, letters, comments, editorials, and non-peer-reviewed papers