It is known that there is lexical variation in NGT, which originated from the different deaf schools in the Netherlands (see also SOCIO-HISTORICAL BACKGROUND 1.1). In particular, signs from the Southern region used to be significantly different from signs in the rest of the Netherlands (Schermer 2003; Schermer & Harder 1986). This may have resulted from the fact that a different sign system was used at the school in Sint Michielsgestel than in Groningen, and from the different policies at the schools regarding the use of signs (Schermer 2003). There was regular contact between deaf people in the North and in the West of the Netherlands, which explains why Schermer & Harder (1986) found quite some similarities in the signs from these regions. However, nowadays, specifically the signs from Groningen on the one hand and from Western regions on the other are considered to be quite different.
Little is known about lexical variation that is due to other sociolinguistic factors (e.g. gender or age), or about regional grammatical differences. The few studies that looked at grammatical differences related to sociolinguistic factors (age, gender, region), did not find evidence for such variation (e.g. Bank 2014; Coerts 1992; Klomp 2019). Two small exceptions are (i) the finding that the distribution of handshapes is slightly different per region, which is related to the different lexicons (further addressed in PHONOLOGY, Chapter 1), and (ii) the finding that mouthings (PHONOLOGY 1.5.2) seem to be used less frequently by higher educated signers compared to lower educated signers (Bank 2014).