Table 1.

Cross-syndromic descriptions of the PPA Progression Planning Aid (PPA²) stages

PPA stage	Daily life impact	Care implications
1: Very mild	This stage reflects the earliest clinical manifestations of PPA, but the person may not seek help, attributing problems to stress or ageing. Symptoms may be intermittent, difficult for the person to describe, or recognised only by those who know them well or in hindsight.	Definitive diagnosis of PPA may not be possible but clinical vigilance is required and specialist referral may be helpful
2: Mild	Communication and other less prominent problems with everyday activities are generally evident to others as well as to the person themselves (though sometimes insight may be lacking).	By this stage, a confident diagnosis of PPA by an experienced clinician should be possible
3: Moderate	The person may now require help managing certain aspects of day-to-day life and will generally have to stop working. Communication difficulties tend to frustrate important goals and social activities.	Engagement of supports and local services becomes essential
4: Severe	The person now requires support with many aspects of daily living and communication is increasingly difficult. They may no longer be able to live independently.	Care needs are complex and evolving, and safety concerns are paramount along with interventions to mitigate caregiver mental health issues and burnout
5: Very severe	Cognitive and behavioural changes are more global in nature, and many are common to all PPA syndromes. Meaningful communication is rarely possible. The person is likely to need help with daily personal care including toileting, and physical symptoms will have developed to the extent that mobility is significantly affected.	Significant complications and comorbidities may require management in their own right (e.g., the consequences of falls, immobility and/or incontinence)
6: Profound	Communication is now no longer possible. The person may lose their ability to respond to their environment and becomes largely immobile	Focus should now be placed on end-of-life care and bereavement support

The Table shows cross-syndromic stage labels that were presented to survey respondents and refined based on feedback, and which cross-reference to Figures 2-4 and Tables S1-S3. The stage labels align with those used in the Frontotemporal Dementia Rating Scale¹³. The text in the ‘Daily life impact’ column was developed during exploratory work and adapted from descriptors used in posterior cortical atrophy³³ and Alzheimer’s disease¹². A Spanish translation of this Table is given in Supplementary materials online (Table S5). PPA, primary progressive aphasia.