Smith and Lloyd showed that mother's do treat boy and girl babies differently, in line with sex-role stereotypes
Limitation validity of BSRI
It lacks temporal validity it is historically and socially biased. Definitions of masculinity and femininity were created over 40 years ago! Hoffmann and Borders asked a group of 400 undergraduates to consider the definitions from Bems original study
They only kept two of the original definitions! They failed to secure 75% agreement on definitions so BEM scale may no longer be relevant! Today we have non binary, metrosexual, ladettes etc..all do not fit definition.
Smith and Lloyd (1978)
The mothers (sample size 32) were videotaped playing for 10 minutes with a baby (not their own child). The baby was six months old and dressed and named as a boy or a girl (the clothes/ names were not always consistent with sex), Seven toys were present: two stereotypically masculine, two feminine and three neutral. If a mother thought she was playing with a boy, she verbally encouraged more motor activity and offered gender-appropriate toys.
In other words, mothers responded to the perceived sex of the infant, in line with typical gender expectations.
Reliability of the BSRI A strength of the BSRI is its high reliability.
Research has demonstrated high test-retest reliability for the BSRI over a four-week period, correlations range from .76 to .94 (Bem, 1981). A short form of the scale has been developed using just 30 items and has a good correlation of 90 with the original. Having a shorter form improved the internal reliability of the test because the less socially desirable terms were removed, such as 'gulible' and 'childlike".
High reliability is vital for any test to produce meaningful results.