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Item Validation and reproducibility of an iodine and selenium specific food frequency questionnaire in breastfeeding women : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Nutrition and Dietetics at Massey University, Albany, New Zealand(Massey University, 2023) Bertasius, CharlotteBackgrounds: New Zealand has poor levels of iodine and selenium in its food sources. During lactation, women have increased selenium and iodine requirements, as their breastfeeding infant relies on their intake, putting them at increased risk of deficiency. Thyroid function is impacted by iodine and selenium status, and if these nutrients are low can cause consequences for the mother and breastfed infant. Dietary assessment methods, such as a Food Frequency Questionnaire (FFQ), can be utilised to assess nutrient intake, and validating an FFQ shows that the questionnaire can be used on the intended population to predict nutrient intake. To the best of our knowledge, New Zealand currently does not have a valid iodine and selenium specific FFQ for breastfeeding women. Due to this population risk with iodine and selenium, it is justified to test the validity and reproducibility of this FFQ on breastfeeding women in New Zealand. Aim: The aim of this study is to assess the validity and reproducibility of an iodine and selenium specific Food Frequency Questionnaire for breastfeeding women living in New Zealand. Methods: As part of the Mother and Infant Nutrition Investigation study (MINI), data was collected from breastfeeding mothers from three months to 12 months postpartum (PP). Participants (n = 87) were administered an iodine and selenium specific FFQ at three months and a four-day diet diary (4DDD). To assess reproducibility the FFQ was readministered at 12 months PP (FFQ2). FFQ1 was validated via 4DDD and selected biomarkers (urinary and breastmilk iodine concentrations and plasma selenium); statistical analysis was used, including Wilcoxon signed ranked test, Spearman’s correlation, cross-classifications, weighted kappa statistics, Bland Altman plots, the same statistical analysis carried out to assess reproducibility between FFQ1 and FFQ2. Results: For the validation, the correlation observed ranged from 0.317 (selenium) to 0.532 (total iodine) between the FFQ and 4DDD and for FFQ to EIB, 0.146 (selenium) and 0.155 (total iodine). Cross-classifications majority of the nutrient groups were >50% correctly classified (32.9% (selenium) to 71.6% (iodine food only)) when comparing the FFQ to 4DDD. Most of the groups were <10% misclassified (1.37% (iodine and salt) to 11.0% (selenium)). For the FFQ to EIB, the correctly classified participants were 50% (iodine) and 73.1% (selenium), and the grossly misclassified participants were 16.35% (iodine) and 3.4% (selenium). For FFQ to 4DDD, the weighted kappa values showed poor agreement (k<0.21) for two groups and fair agreement (k 0.21-0.41) for three groups. For EIB, the weighted kappa showed poor agreement (k<0.21) for four groups and fair agreement (k 0.21-0.41) for one. The Bland-Altman plots showed fair agreement for the difference between FFQ1 to 4DDD or EIB. For reproducibility, the correlation between FFQ1 and FFQ2 was 0.625 (iodine) and 0.429 (selenium). Cross-classification for correctly classified participants was >50% for iodine; for selenium and iodine, <10% were grossly misclassified. The weight kappa value showed poor agreement (k0.21) for both iodine and selenium. Conclusion: The FFQ showed reasonable validity when assessing iodine and selenium intake using the FFQ for breastfeeding women in New Zealand and showed good reproducibility for iodine and selenium. This FFQ could be used in future research on this population and could be used in primary care as a convenient way to assess iodine and selenium intake for breastfeeding women in New Zealand.Item Examining the generalizability of research findings from archival data(PNAS, 2022-07-26) Delios A; Clemente EG; Wu T; Tan H; Wang Y; Gordon M; Viganola D; Chen Z; Dreber A; Johannesson M; Pfeiffer T; Generalizability Tests Forecasting Collaboration; Uhlmann ELThis initiative examined systematically the extent to which a large set of archival research findings generalizes across contexts. We repeated the key analyses for 29 original strategic management effects in the same context (direct reproduction) as well as in 52 novel time periods and geographies; 45% of the reproductions returned results matching the original reports together with 55% of tests in different spans of years and 40% of tests in novel geographies. Some original findings were associated with multiple new tests. Reproducibility was the best predictor of generalizability—for the findings that proved directly reproducible, 84% emerged in other available time periods and 57% emerged in other geographies. Overall, only limited empirical evidence emerged for context sensitivity. In a forecasting survey, independent scientists were able to anticipate which effects would find support in tests in new samples.Item Determining the validity and reproducibility of the Healthy Heart Food Index : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Science in Nutrition and Dietetics at Massey University, Albany, New Zealand(Massey University, 2019) Guy, HarrietBackground: Diet quality is associated with cardiovascular disease (CVD) risk, and the New Zealand (NZ) Heart Foundation has produced dietary guidelines aimed at reducing CVD risk for adult New Zealanders. At present, there is no valid and reproducible diet quality index for older adults living in NZ, which focuses on CVD risk. Aim: To develop and determine the construct validity and reproducibility of the Healthy Heart Food index (HHFI) for measuring dietary patterns in older adults living in New Zealand. Method: The HHFI was developed based upon NZ Heart Foundation Guidelines. To assess HHFI reproducibility, 298 community dwelling participants aged 65-74 years completed the HHFl twice approximately four-weeks apart. To validate the index, 142 of these participants completed a four-day food record (4DFR). Construct validity was explored using Spearman's correlation coefficients and linear contrast analysis of selected nutrients from the 4DFR. Spearman's correlation coefficients, Wilcoxon ranked-signed tests, cross-classification, the weighted kappa statistic, and a Bland-Altman plot were used to assess HHFl reproducibility. Results: Mean HHFl total scores were 693i10.8 and 68.9i11.1 from the first and second HHFl administrations respectively. These scores were positively correlated (r= 0.662, P<0.001) and cross-classification showed 55.4% of participants were categorised into the same fertile and 6.3% were grossly misclassified. The weighted kappa statistic was K: 0.43, indicating moderate agreement between HHFI total scores. For construct validity, iron (r= 0.201), vitamin C (r= 0.174), and niacin (r= 0.205) (all P<0.05), and protein (r= 0.277), polyunsaturated fatty acids (r= 0.236), dietary fibre (r= 0.307), vitamin (r= 0.205), folate (r= (1268), potassium (r= 0.246), magnesium (r= 0.300), phosphorus (r= 0.281), zinc (r= 0.276), and selenium (r= 0.222) (all P<0.01), were positively correlated with the HHFI total score. Saturated fat and cholesterol were negatively correlated (r= -0.097 and -0.035 respectively) with the HHFI total score, however this was a non-significant association (P>0.05). Linear contrast analysis showed a significant positive association between polyunsaturated fat, monounsaturated fat, dietary fibre, potassium, folate (P<0.05), vitamin E (P<0.01), and magnesium (P<0.005) and HHFI total scores. Conclusion: Moderate adherence to the HHFI was shown in this population sample. Results indicate the HHFI demonstrated construct validity and good reproducibility for assessing CvD-related diet quality in older adults living in New Zealand. Further research is needed to examine the predictive validity of this index in relation to CVD risk.Item Determining the relative validity and reproducibility of a food frequency questionnaire to assess food group intake in high performing athletes : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Science in Nutrition and Dietetics, Massey University, Albany, New Zealand(Massey University, 2018) Stockley, DaynaBackground: Optimal nutrition is essential for high performing athletes in order to train effectively, optimise recovery and improve their performance. Given the differences in dietary requirements and practices that exist between athletes and the general population, dietary assessment tools designed specifically for athletes are required. Food frequency questionnaires (FFQs) are commonly used to assess habitual dietary intake as they are inexpensive, quick and easy to administer. Currently there are no athlete-specific, up-to-date, valid and reproducible FFQs to assess food group intake of athletes. This study aims to determine the relative validity and reproducibility of an athlete-specific FFQ against an estimated four day food record (4DFR) to assess food group intake in high performing athletes. Methods: Data from 66 athletes (24 males, 42 females) representing their main sport at regional level or higher and aged 16 years and over, was collected as part of a validation study in 2016. Athletes completed the athlete-specific FFQ at baseline (FFQ1) and four weeks later (FFQ2) to assess reproducibility. An estimated 4DFR was completed between these assessments to determine the relative validity of the FFQ1. Foods appearing in the 4DFR were classified into the same 129 food groups as the FFQ, and then further classified into 28 food groups in gram amounts. Agreement between the two methods for intake of food group and core food group intake was assessed using Wilcoxon signed rank tests, Spearmans correlation coefficients, cross classification with tertiles, the weighted kappa statistic and Bland-Altman analysis. Results: The FFQ overestimated intake for 17 of 28 food groups compared with the 4DFR (p<0.05). Correlations ranged from 0.11 (processed foods) to 0.78 (tea, coffee & hot chocolate), with a mean of 0.41. Correct classification of food groups into the same tertile ranged from 35.4% (starchy vegetables) to 55.5% (fats & oils). Misclassification into the opposite tertile ranged from 4.6% (legumes) to 15.4% (starchy vegetables; sauces & condiments). The weighted kappa demonstrated fair to moderate agreement (k=0.21-0.60) for food groups. Bland-Altman plots suggested that for most of food groups, the difference between FFQ1 and the 4DFR increased as the amount of each food group consumed increased. Intake from FFQ1 was significantly higher than from FFQ2 for 13 of 28 food groups. All effect sizes were small (r=0.1). Reproducibility correlations ranged from 0.49 (potato chips; fats & oils) to 1.00 (tea, coffee & hot chocolate), with a mean of 0.65. For the 23 food groups classified into tertile, 20 had >50% of participants correctly classified, <10% grossly misclassified, and 20 demonstrated moderate to good agreement (k=0.61-0.80). The exceptions were dairy; fats & oils; and processed foods & drinks which presented fair agreement (k=0.21-0.40). Conclusions: The FFQ showed reasonable validity and good reproducibility for assessing food group intake in high performance athletes in New Zealand. The FFQ could be used in future research as a convenient, cost-effective and simple way to obtain athletes’ food group intake, and identify those who could benefit from interventions to improve their nutritional adequacy and potentially their athletic performance.Item Retract p < 0.005 and propose using JASP, instead(F1000Research, 12/12/2017) Perezgonzalez JD; Frías-Navarro MDSeeking to address the lack of research reproducibility in science, including psychology and the life sciences, a pragmatic solution has been raised recently: to use a stricter p < 0.005 standard for statistical significance when claiming evidence of new discoveries. Notwithstanding its potential impact, the proposal has motivated a large mass of authors to dispute it from different philosophical and methodological angles. This article reflects on the original argument and the consequent counterarguments, and concludes with a simpler and better-suited alternative that the authors of the proposal knew about and, perhaps, should have made from their Jeffresian perspective: to use a Bayes factors analysis in parallel (e.g., via JASP) in order to learn more about frequentist error statistics and about Bayesian prior and posterior beliefs without having to mix inconsistent research philosophies.Item Not the time or the place: the missing spatio-temporal link in publicly available genetic data.(Blackwell Publishing Ltd, 2015-08) Pope LC; Liggins L; Keyse J; Carvalho SB; Riginos CGenetic data are being generated at unprecedented rates. Policies of many journals, institutions and funding bodies aim to ensure that these data are publicly archived so that published results are reproducible. Additionally, publicly archived data can be 'repurposed' to address new questions in the future. In 2011, along with other leading journals in ecology and evolution, Molecular Ecology implemented mandatory public data archiving (the Joint Data Archiving Policy). To evaluate the effect of this policy, we assessed the genetic, spatial and temporal data archived for 419 data sets from 289 articles in Molecular Ecology from 2009 to 2013. We then determined whether archived data could be used to reproduce analyses as presented in the manuscript. We found that the journal's mandatory archiving policy has had a substantial positive impact, increasing genetic data archiving from 49 (pre-2011) to 98% (2011-present). However, 31% of publicly archived genetic data sets could not be recreated based on information supplied in either the manuscript or public archives, with incomplete data or inconsistent codes linking genetic data and metadata as the primary reasons. While the majority of articles did provide some geographic information, 40% did not provide this information as geographic coordinates. Furthermore, a large proportion of articles did not contain any information regarding date of sampling (40%). Although the inclusion of spatio-temporal data does require an increase in effort, we argue that the enduring value of publicly accessible genetic data to the molecular ecology field is greatly compromised when such metadata are not archived alongside genetic data.
