Table 2.
Validity and reliability of the reviewed food and nutrition literacy tools for children and adolescents
| Tool author (year) | Validity | Reliability | |||
|---|---|---|---|---|---|
| Content validity: covers all constructs | Face validity: appears to measure construct of interest | Structural/construct validity: measures the concept intended to measure | Internal consistency: measures if several items measure the same construct | Test-retest reliability: measures the consistency of a test over time | |
| M-FNLIT Khorramrouz (2021) |
Content validity assessed and evaluated by 2-round Delphi consensus of 20 experts Findings from 2-rounds (respectively): CVR: 0·72 and 0·92 CVI: 0·92 and 0·98 |
Face validity assessed using a convenience sample of 10 children aged 9–12 years. Impact scores were also calculated by evaluating the frequency and importance of items | Structural/Construct validity assessed using confirmatory factory analysis to examine whether the data fits the measurement model | All 36 items: Cronbach α = 0·88 Internal consistency across 6 subscales ranged from α = 0·22–80 |
Test re-test all 36 items: ICC = 0·95 Test re-test of 6 subscales: ICC = 0·73–0·91 |
| FNLQ-SC Liu (2021) |
Content validity was assessed by the Pearson correlation coefficient Pearson correlation coefficients between each dimension and the overall questionnaire ranged from 0·370 to 0·877 |
Not reported | Structural/Construct validity assessed using exploratory factor analysis to explore whether the statements in the questionnaire reflected the conceptual framework, in addition to confirmatory factor analysis The Kaiser-Meyer-Olkin test showed sampling adequacy (KMO = 0·738), and Bartlett’s test confirmed that factor analysis was appropriate (P < 0·001) |
All 50 items: Cronbach α = 0·70 Internal consistency across 5 subscales ranged from α = 0·15–0·45 |
Not reported |
| FL Tool Stjernqvist (2021) |
Content validity assessed and validated by a group of experts based on Benn’s (2014) model of FL(38) | Face validity assessed using 2 focus group interviews with 12 schoolchildren | Structural/Construct validity assessed using confirmatory factory analysis in reducing items and comparing models Convergent validity assessed using a health literacy instrument for school-aged children (2016)(40); significant positive association for the total FL scale (β = 9·82, P < 0·001) and its 5 competencies Convergent validity assessed using food intake as an outcome with a food frequency index (2014); significant association for the total FL scale (β = 2·32, P < 0·001) and its 5 competencies |
All 37 items: Cronbach α = 0·85 Internal consistency across 5 subscales ranged from α = 0·50–0·73 |
Test re-test all 37 items: ICC = 0·92 Test re-test of 5 subscales: ICC = 0·76–0·88 |
| FNLAT Ashoori (2020) |
Content validity assessed by literature review, expert panels and evaluated by Delphi consensus of 19 experts CVI: >0·90 |
Face validity assessed using cognitive interviews among 10 high school students | Construct validity assessed using PCA and CFA. The Kaiser–Meyer–Olkin test showed sampling adequacy (KMO = 0·728), and Bartlett’s test confirmed that factor analysis was appropriate (P < 0·001). |
All 60 items: Cronbach α = 0·84 Internal consistency across all subscales ranged from α = 0·71–0·82, except for the subscales ‘critical analysis of information’ (α = 0·64) and ‘food label reading skills’ α = 0·56) |
Test re-test all 60 items: ICC = 0·93 Test re-test of 6 subscales: ICC = 0·59–0·90 |
| THAI-NLAT Deesamer (2020) | Content validity assessed and validated by 7 experts based on Velardo’s (2015)(9) concepts for NL in addition to assessing item-content validity | Face validity assessed using cognitive interviews among 10 Thai adolescents | Structural/Construct validity assessed using Known Group Technique; the healthy group (based on energy distribution and sugar intake) had nutrition literacy scores significantly higher than the unhealthy group Convergent validity assessed using the coefficient correlation analysis between the THAI-NLAT and the Thai Healthy Eating Index; significant positive relation between energy distribution and THAI-NLAT score of energy balance (r = 0·131, P = 0·021) |
All 61 items: KR-20 = 0·83 Internal consistency assessed through item-subscale correlation, and ranged from r = 0·627–0·781(P < 0·01) |
Not reported |
| Preschool-FLAT Tabacchi (2020) | Content validity assessed by a panel of 5 experts based on constructs adapted by Vidgen (2014)(6)
CVI = 0·94 CVR = 0·88 |
Not reported | Structural/Construct validity assessed using a SEM Discriminant validity assessed using a convenient intervention subgroup v. control group; unpaired t-test revealed statistical significance between FL score and those who received the intervention than those who did not receive it (mean 15·1 v. 7·1, P < 0·001) |
All 16 items: Cronbach α = 0·77 Internal consistency across 4 subscales ranged from α = 0·73–0·76 |
Not reported |
| TFLAC Amin (2019) |
Content validity assessed using 2-round modified Delphi approach with 16 panelists CVR Round 1 = 0·40 CVR Round 2 = 0·70 |
Not reported | Not reported | Internal consistency across all food literacy domains (except cooking knowledge) ranged from: Cronbach α = 0·80–0·98, with cooking knowledge: α = 0·63 | Test re-test across all food literacy domains ranging from: ICC = 0·64–0·70 (P < 0·001) |
| CNL-E Naigaga (2018) |
Not reported | Not reported | Structural/Construct validity assessed using the Rasch model showed a good fit with independent items, representing a well-targeted measurement | All 5 items: Cronbach α = 0·90 | PSI = 0·88 for the original data set (with missing values) |
| FNLIT Doustmohammadian (2017) |
Content validity assessed by a panel of 8 experts based on Nutbeam’s hierarchical model of health literacy(41)
CVI = 0·92 CVR = 0·87 |
Face validity assessed using interviews among 15 students | Structural/construct validity assessed using EFA and CFA. The EFA suggested a 6-factor construct with the CFA indicating acceptable fit indices among the proposed models | Internal consistency across the FNLIT scale and its subscales (except critical skill subscale) ranged from: Cronbach α = 0·71–0·80, with critical skill subscale α = 0·48 | Test re-test all 46 items: ICC = 0·89 with its subscales ranged from: ICC = 0·78–0·91 |
| MBL Tool Williams (2017) | Content validity assessed by a panel of 29 experts | Face validity assessed using cognitive interviews among 24 students | Not reported | Pilot sample: Reliability in all 20 MBL items (pretest): ωt = 0·87, and (posttest) ωt = 0·91, while 7 SE items (pretest): ωt = 0·78, and (posttest) ωt = 0·83 Internal consistency assessed by in MBL items: Ordinal α = 0·86 (pretest), and α = 0·90 (posttest) while SE items: Ordinal α = 0·78 (pretest), and α = 0·83 (postest) |
Not reported |
| CNL Tool Guttersrud (2015) | Not reported | Not reported | Structural/Construct validity assessed using the Rasch model showed that the subscales measure the defined constructs | Internal consistency in the EDB scale and the SE in science scale were: Cronbach α = 0·86 and α = 0·92, respectively | The PSI were 0·79 and 0·90 for the EDB scale and the SE in science scale, respectively |
| FLLANK Reynolds (2012) | Not reported | Not reported | Structural/Construct validity assessed using between-group differences in ONQI scores generated from each product used in the FLLANK. Mean ONQI scores for the correct item responses were significantly higher than the mean ONQI scores that were incorrect (27·4 ± 9·4 v. 16·2 ± 9·4; P = 0·01) | All 10 items: Cronbach α = 0·77 | Test re-test all 10 items: ICC = 0·68 |
CFA; confirmatory factor analyses; CVI, content validity index; CVR, content validity ratio; M-FNLIT, modified food and nutrition literacy; FNLQ-SC, food and nutrition literacy questionnaire for Chinese school-age children; FL, food literacy; THAI-NLAT, Thai-nutritional literacy assessment tool, preschool-FLAT, preschool-food literacy assessment tool; TFLAC, tool for food literacy assessment in children; CNL-E, Critical nutrition literacy-evaluation; MBL tool, menu board literacy tool; FLLANK, food label literacy for applied nutrition knowledge questionnaire; PCA, principal component analysis; SEM, structural equation model; EFA, explanatory factor analyses; ONQI, overall nutritional quality index; α, alpha; ICC, intraclass coefficient; KR-20, Kuder-Richardson-20; PSI, person separation index; ωt, McDonald’s omega; SE, self-efficacy; EDB, engagement in dietary behavior.