title: Towards robust and repeatable sampling methods in eDNA-based studies

authors: Dickie, Ian A.

subjects: Science & Technology

abstract: DNA‐based techniques are increasingly used for measuring the biodiversity (species presence, identity, abundance and community composition) of terrestrial and aquatic ecosystems. While there are numerous reviews of molecular methods and bioinformatic steps, there has been little consideration of the methods used to collect samples upon which these later steps are based. This represents a critical knowledge gap, as methodologically sound field sampling is the foundation for subsequent analyses. We reviewed field sampling methods used for metabarcoding studies of both terrestrial and freshwater ecosystem biodiversity over a nearly three‐year period (n = 75). We found that 95% (n = 71) of these studies used subjective sampling methods and inappropriate field methods and/or failed to provide critical methodological information. It would be possible for researchers to replicate only 5% of the metabarcoding studies in our sample, a poorer level of reproducibility than for ecological studies in general. Our findings suggest greater attention to field sampling methods, and reporting is necessary in eDNA‐based studies of biodiversity to ensure robust outcomes and future reproducibility. Methods must be fully and accurately reported, and protocols developed that minimize subjectivity. Standardization of sampling protocols would be one way to help to improve reproducibility and have additional benefits in allowing compilation and comparison of data from across studies.

text: Towards robust and repeatable sampling methods in eDNA-based studies DNA‐based techniques are increasingly used for measuring the biodiversity (species presence, identity, abundance and community composition) of terrestrial and aquatic ecosystems. While there are numerous reviews of molecular methods and bioinformatic steps, there has been little consideration of the methods used to collect samples upon which these later steps are based. This represents a critical knowledge gap, as methodologically sound field sampling is the foundation for subsequent analyses. We reviewed field sampling methods used for metabarcoding studies of both terrestrial and freshwater ecosystem biodiversity over a nearly three‐year period (n = 75). We found that 95% (n = 71) of these studies used subjective sampling methods and inappropriate field methods and/or failed to provide critical methodological information. It would be possible for researchers to replicate only 5% of the metabarcoding studies in our sample, a poorer level of reproducibility than for ecological studies in general. Our findings suggest greater attention to field sampling methods, and reporting is necessary in eDNA‐based studies of biodiversity to ensure robust outcomes and future reproducibility. Methods must be fully and accurately reported, and protocols developed that minimize subjectivity. Standardization of sampling protocols would be one way to help to improve reproducibility and have additional benefits in allowing compilation and comparison of data from across studies.

year: 2018

title: Puarenga Stream alum dosing – Summary of effects on lake biota 2015

authors: Ling, Nicholas

abstract: Continuous alum dosing of the Puarenga Stream commenced in early 2010 to reduce inflows of dissolved reactive phosphorus to Lake Rotorua. Analyses of bioaccumulation in the tissues of macrobiota were undertaken in February 2015 for comparison to comparable samples obtained prior to and since the commencement of alum dosing to satisfy annual resource consent conditions 8.7 and 8.8 of resource consent 65559.
No significant effects of alum dosing could be distinguished. Bioavailable aluminium in the vicinity of Sulphur Bay appears to be primarily influenced by the major geothermal activity of this region. Lake water chemistry in the vicinity of Sulphur Bay is heavily influenced by the direction of geothermal flows emanating from the Bay. No significant differences in aluminium bioaccumulation were observed in any species compared to samples obtained prior to the commencement of alum dosing. Continuous alum dosing of the Puarenga Stream since 2010 apparently has not resulted in adverse effects to Lake Rotorua shoreline biota nor caused any apparent increase in aluminium bioaccumulation in lake biota in the vicinity of Sulphur Bay.

text: Puarenga Stream alum dosing – Summary of effects on lake biota 2015 Continuous alum dosing of the Puarenga Stream commenced in early 2010 to reduce inflows of dissolved reactive phosphorus to Lake Rotorua. Analyses of bioaccumulation in the tissues of macrobiota were undertaken in February 2015 for comparison to comparable samples obtained prior to and since the commencement of alum dosing to satisfy annual resource consent conditions 8.7 and 8.8 of resource consent 65559.
No significant effects of alum dosing could be distinguished. Bioavailable aluminium in the vicinity of Sulphur Bay appears to be primarily influenced by the major geothermal activity of this region. Lake water chemistry in the vicinity of Sulphur Bay is heavily influenced by the direction of geothermal flows emanating from the Bay. No significant differences in aluminium bioaccumulation were observed in any species compared to samples obtained prior to the commencement of alum dosing. Continuous alum dosing of the Puarenga Stream since 2010 apparently has not resulted in adverse effects to Lake Rotorua shoreline biota nor caused any apparent increase in aluminium bioaccumulation in lake biota in the vicinity of Sulphur Bay.

year: 2016

title: Real world initiation of newly funded empagliflozin and dulaglutide under special authority for patients with type 2 diabetes in New Zealand

authors: Chepulis, Lynne Merran

subjects: GLP1RA

abstract: Background: Type 2 diabetes (T2D) is sub-optimally managed for many in Aotearoa New Zealand, and disproportionately affects Māori and Pacific peoples. In February 2021, SGLT2i/GLP1RA agents were funded for use for the first time with prioritisation for Māori, Pacific and those with cardiovascular and/or renal disease or risk (CVRD). This study evaluates the impact of health system factors on initiation of SGLT2i/GLP1RA therapy. 

Methods: Primary care data was collected for patients with T2D aged 18–75 years from four primary care organisations (302 general practices) in the Auckland / Waikato region of New Zealand (Feb 2021 – July 2022). Initiation of SGLT2i/GLP1RA therapy was reviewed by patient (age, gender, ethnicity, CVRD status) and health system variables (funding, provider type, staffing, patient numbers, rurality, after-hours access). Logistic regression was used to estimate the odds ratio of a patient being dispensed SGLT2i/GLP1RA. 

Results: Of 57,743 patients with T2D, 22,331 were eligible for funded SGLT2i/GLP1RA access and 10,272 of those (46.0%) were prescribed. Initiation of therapy was highest in Māori (50.8%) and Pacific (48.8%) patients (vs. 36·2–40·7% of other ethnic groups; P < 0.001), but was comparable in those with and without CVRD (47·1% vs. 48·9%; P = 0.2). Prescribing was highest in practices with higher doctor/patient numbers, low-cost fees, Māori health providers and clinics without after-hours access.

Conclusion: Prioritised access for SGLT2i/GLP1RA appears to be associated with a reduced health equity gap for Māori and Pacific patients with T2D in NZ, but work is required to improve prescribing for patients with CVRD.

text: Real world initiation of newly funded empagliflozin and dulaglutide under special authority for patients with type 2 diabetes in New Zealand Background: Type 2 diabetes (T2D) is sub-optimally managed for many in Aotearoa New Zealand, and disproportionately affects Māori and Pacific peoples. In February 2021, SGLT2i/GLP1RA agents were funded for use for the first time with prioritisation for Māori, Pacific and those with cardiovascular and/or renal disease or risk (CVRD). This study evaluates the impact of health system factors on initiation of SGLT2i/GLP1RA therapy. 

Methods: Primary care data was collected for patients with T2D aged 18–75 years from four primary care organisations (302 general practices) in the Auckland / Waikato region of New Zealand (Feb 2021 – July 2022). Initiation of SGLT2i/GLP1RA therapy was reviewed by patient (age, gender, ethnicity, CVRD status) and health system variables (funding, provider type, staffing, patient numbers, rurality, after-hours access). Logistic regression was used to estimate the odds ratio of a patient being dispensed SGLT2i/GLP1RA. 

Results: Of 57,743 patients with T2D, 22,331 were eligible for funded SGLT2i/GLP1RA access and 10,272 of those (46.0%) were prescribed. Initiation of therapy was highest in Māori (50.8%) and Pacific (48.8%) patients (vs. 36·2–40·7% of other ethnic groups; P < 0.001), but was comparable in those with and without CVRD (47·1% vs. 48·9%; P = 0.2). Prescribing was highest in practices with higher doctor/patient numbers, low-cost fees, Māori health providers and clinics without after-hours access.

Conclusion: Prioritised access for SGLT2i/GLP1RA appears to be associated with a reduced health equity gap for Māori and Pacific patients with T2D in NZ, but work is required to improve prescribing for patients with CVRD.

year: 2025