Bias Collection of Data

This question is not clear as the timeframe isn't stated. Is the survey referring to the use of handphone in 1 day or in 1 entire week? When crafting surveys, you should pilot the survey and check on your participant's understanding of each item during a post-survey interview.

This is a double-barreled item. Respondents who feel that teachers were nice to them but their classmates weren't might not be sure whether to indicate agree or disagree. Instead, the survey should have 2 items: My teachers are nice to me. My classmates are nice to me.

The response options for this item is too limited. Some survey respondents may have 5 or more siblings.