Background Recent diagnostic criteria for progressive supranuclear palsy (PSP) by the Movement Disorder Society (MDS) operationalise recently recognised subtypes, beyond the ‘classical’ Richardson phenotype (PSP-RS): predominant parkinsonism (PSP-P), predominant gait freezing (PSP-PGF), and frontal-cognitive- behavioural presentations (PSP-F).

Aims To evaluate the proportion of patients fulfilling MDS compared with previous NINDS-SPSP criteria; to establish the number of patients fulfilling operationalised subtypes criteria; and to explore the evolution of PSP subtypes.

Methods A retrospective case note review study of 201 patients clinically diagnosed with PSP in a combined behavioural neurology and movement disorders service over a 10-year period.

Results Of 201 patients at first presentation, 187 met MDS-PSP criteria (157 probable, 8 possible, 22 sug- gestive) compared with 152 for NINDS-SPSP criteria. The number of probable PSP patients fulfilling opera- tionalised subtype criteria were: 125 PSP-RS, 111 PSP-P, 5 PSP-PGF, and 37 PSP-F. Notably, 100 patients met criteria for more than one subtype.

Conclusion MDS criteria allowed earlier PSP diagnosis than NINDS-SPSP criteria and captured a range of phenotypic subtypes. Further analysis will address the issue of determining subtype predominance and will explore the natural history of PSP phenotypes, with particular reference to frontal-cognitive- behavioural presentations.