Table 1 The differences between the original and revised DSRBQ versions

Part 1

A total of 28 items:

• Demographic characteristics (n = 9), including age, gender, ethnicity, education, marital status, employment, income and health conditions

• Personal dietary practice (n = 12):

  • 3 items measured using categorical variable scales

  • 5 items measured using 5–point Likert scales ranging from ‘daily (1) to never (5)’, ‘never (1) to always (5)’ and ‘very light (1) to very salty (5)’

  • 3 items requiring participants to directly answer the number of meals being consumed at home and the percentage of food consumed at home vs away from home

  • 1 binary scale (yes/no) items

• Salt–related health education/medical advice that the participant has received (n = 7), measured using a binary scale (yes/no)

A total of 22 items:

• Demographic characteristics (n = 9), including age, gender, place of birth, education, marital status, employment, income and health conditions

• Personal dietary practice (n = 9):

  • 3 items measured using categorical variable scales

  • 3 items measured using 5–point Likert scales ranging from ‘daily (1) to never (5)’, ‘never (1) to always (5)’ and ‘very light (1) to very salty (5)’

  • 2 items requiring participants to directly answer the number of meals being consumed at home and the percentage of food consumed at home vs away from home

  • 1 binary scale (yes/no) items

• Salt–related health education/medical advice that the participant has received (n = 4), measured using a binary scale (yes/no)

• 6 items (Items 8, 13,14, 22, 26 and 27) were removed from the questionnaire because:

  • Item 8 was not relevant to the Chinese Australian lifestyle (I–CVI = 0.50)

  • Items 13 and 14 were related to the cooking style. However, the practices vary according to the participants’ background. Chinese people from different parts of Asia may interpret the questions differently

  • Items 22, 26 and 27 (I–CVI = 0.67). The questions were not related to the salt reduction strategies in Australia

• Item 3 was changed from ‘ethnic groups in China, eg. Han, Zhuang, Hui, etc.’ to the ‘place of birth’

• Item 6 – the weekly income scale was changed and aligned with the 2011 Census, Personal Income Ranges (ABS, 2016)

• Item 11 – the words ‘Beijing local government’ was removed from the answer options

Part 2

• Salt–related health knowledge (n = 6) measured using categorical variable scales

• Salt–related health knowledge (n = 6) measured using categorical variable scales

• No change

Part 3

A total of 47 items forming six subscales:

• Perceived threat (n = 5)

• Knowledge/perceived susceptibility to and severity of the disease (n = 6)

• Perceived benefits of action subscale (n = 3)

• Perceived benefits of using a measuring spoon (n = 3)

• Likelihood of following the recommended interventions (n = 10)

• Perceived barriers (n = 20)

A total of 45 items forming six subscales:

• Perceived threat (n = 5)

• Knowledge/perceived susceptibility to and severity of the disease (n = 6)

• Perceived benefits of action subscale (n = 3)

• Perceived benefits of using a measuring spoon (n = 3)

• Likelihood of following the recommended interventions (n = 10)

• Perceived barriers (n = 18)

• Two Likert scale items (Items 28 and 29) were removed because they were related to the measuring spoon given by the local government in Beijing, China