Table 1.

Studies investigating the correlation between neuropsychological test scores and CTG repeat expansion size in DM1.

Authors*	Number of patients	Tests	Main conclusion
Turnpenny et al. [34]	55	WAIS (short version).	Increase in repeat size associated with lower IQ.
Damian et al. [10]	28	Neuropsychological test battery†.	Large repeat size (>1000) associated with cognitive impairment.
Jaspert et al. [33]	14	MMSE, MWT-B, Progressive matrices.	Large repeat size (> 1000) associated with cognitive impairment.
Rubinsztein et al. [9]	36	MMSE, NART, Progressive matrices.	Mild DM1 associated with impaired memory function.
Perini et al. [25]	17	WAIS	CTG correlates with total IQ and non-verbal IQ.
Marchini et al. [13]	24	WAIS	CTG correlates with all IQ measures and short-term memory (Digit span).
Steyaert et al. [14]	24	WISC	CTG correlates with IQ in childhood type of DM1.
Meola et al. [8]	19	Neuropsychological test battery.†	No correlation between CTG repeat size and test performance.
Modoni et al. [24]	70	Neuropsychological test battery.†	No correlation between CTG repeat size and test performance.

* Referred articles are presented in the reference section.

^† Batteries including tests aimed to measure a wide variety of neuropsychological functions. WAIS = Wechsler Adult Intelligence Scale; MMSE = Mini Mental State Examination; MWT-B = Mehrfach- Wahl-Wortschatz-Test; NART = National Adult Reading Test; WISC = Wechslers Adult Intelligence Scale for Children.