Table 1.

Inclusion and exclusion criteria.

Inclusion or exclusion	Criteria	Rationale
Inclusion	Aged 18 or older Having the capacity to consent Having used peer support forums within the past 2 years Symptoms of postpartum psychosis (PP) experienced at any time	Able to give informed consent Ensuring consent is ethically given Forums are evolving quickly [45]; those who used forums longer ago may have had experiences less relevant to current experiences Due to recognition that people with PP can need support for several years after onset, and recognizing that support has changed in recent years [11,12], and wanting to capture information from those who used the forums when support might not have been as available
Exclusion	None beyond self-reported experiences of PP symptoms	No formal mental health diagnosis required as PP is not recognized as a distinct diagnosis [17], and potentially issues of stigma [46] and lack of formal screening measures leading to PP going unrecognized [20]