Fifteen -
item versions
of the scale demonstrate acceptable
reliability (α = 0.79 to 0.87) 46, 47 and studies have worked with only 9
items, namely 3
items per subscale.48 — 50 This study uses a modified version
of the 9 -
item short scale.48 — 50 One
item («I get along with people I come into contact with») was replaced with another
item from the original scale («I really like the people I interact with») based on recommendations that wording in scale
items be as
specific, concrete and non-ambiguous as possible.51 The 9 -
item questionnaire has three subscales with three
items each: autonomy, competency and relatedness.
It is therefore essential that the
reliability and validity
of the SDQ continues to be assessed across differing cultural settings, particularly in situations such as in China, where issues
of tradition or social structure and organization may result in subtle alterations in the meaning
of specific items which could impact on
reliability and validity.