Hi Jin,
You offer a really well-rounded synthesis of the development and validation of a 2-item screen for food insecurity. I appreciate your critique of the authors' reliability evaluation.
I agree that research on validity is needed to ensure that items are functioning the same across groups. Additionally, I'm curious as to how "functioning the same" is defined. In your example, an assessment of depression may not have the same meaning for individuals who have different cultural backgrounds. I imagine that some consider an exact translation appropriate means to develop constructs that function the same across groups without taking into account often misunderstood or unrecognized cultural or cognitive differences, as well. In another example, determining whether a measure for mammography readiness functions the same between women with and without intellectual disabilities requires us to ask how a single cognitive test can be designed to function the same for individuals with a range of cognitive differences.