title: Why does the Engel method work? Food demand, economies of size and household survey methods

authors: Gibson, John

subjects: food demand

abstract: Estimates of household size economies are needed for the analysis of poverty and inequality. This paper shows that Engel estimates of size economies are large when household expenditures are obtained by respondent recall but small when expenditures are obtained by daily recording in diaries. Expenditure estimates from recall surveys appear to have measurement errors correlated with household size. As well as demonstrating the fragility of Engel estimates of size economies, these results help resolve a puzzle raised by Deaton and Paxson (1998) about differences between rich and poor countries in the effect of household size on food demand.

text: Why does the Engel method work? Food demand, economies of size and household survey methods Estimates of household size economies are needed for the analysis of poverty and inequality. This paper shows that Engel estimates of size economies are large when household expenditures are obtained by respondent recall but small when expenditures are obtained by daily recording in diaries. Expenditure estimates from recall surveys appear to have measurement errors correlated with household size. As well as demonstrating the fragility of Engel estimates of size economies, these results help resolve a puzzle raised by Deaton and Paxson (1998) about differences between rich and poor countries in the effect of household size on food demand.

year: 2002-05

title: Sedimentologic and hydrodynamic trends along a modern fluvial to marine transition zone: Mud deposition in the Lower Waihou River, Aotearoa-New Zealand

authors: Roche, Ben

subjects: Process-response

abstract: The fluvial to marine transition zone (FMTZ) is a dynamic environment, subject to a mixture of marine and riverine forcing mechanisms. These processes control deposition of sediments, which can hold valuable natural resources. However, due to the complex process regime, the sedimentary successions from these areas can be difficult to interpret. This study aims to improve depositional models by linking quantified measurements of the active processes to their deposits along the transition zone, using a modern example of these systems, the Waihou River in the North Island of Aotearoa-New Zealand. This study produced three main findings, which are relevant to people researching ancient shallow marine strata: 1) The locus of mud deposition occurs in the middle of the transition zone due the combined influence of depositional and preservational controls. Mixing of marine and freshwater reduces landward, which limits flocculation, and hence, deposition of mud upstream. In contrast, preservation of mud deposits is reduced towards the mouth of the river as a result of faster flow speeds. Midway between these two endpoints is a region where deposition and preservation of mud is the largest within the FMTZ. 2) Fluid mud deposits are poorly preserved in the deepest parts of channels, likely due to the high energy levels in this environment. Nevertheless, our results do not preclude the possibility that significant accumulations may occur in the shallow parts of the cross-channel profile. 3) Mud facies diversity is an indicator of depositional position along the FMTZ. Facies diversity was greatest at the middle observational site, which corresponds to the area that is subject to the most variable process regime. The landward and seaward ends of the transition zone exhibit a greater level of dominance in solely riverine or marine depositional processes, respectively. This study yields new insights into the process-response relationships for mud deposition at the interface of land to sea.

text: Sedimentologic and hydrodynamic trends along a modern fluvial to marine transition zone: Mud deposition in the Lower Waihou River, Aotearoa-New Zealand The fluvial to marine transition zone (FMTZ) is a dynamic environment, subject to a mixture of marine and riverine forcing mechanisms. These processes control deposition of sediments, which can hold valuable natural resources. However, due to the complex process regime, the sedimentary successions from these areas can be difficult to interpret. This study aims to improve depositional models by linking quantified measurements of the active processes to their deposits along the transition zone, using a modern example of these systems, the Waihou River in the North Island of Aotearoa-New Zealand. This study produced three main findings, which are relevant to people researching ancient shallow marine strata: 1) The locus of mud deposition occurs in the middle of the transition zone due the combined influence of depositional and preservational controls. Mixing of marine and freshwater reduces landward, which limits flocculation, and hence, deposition of mud upstream. In contrast, preservation of mud deposits is reduced towards the mouth of the river as a result of faster flow speeds. Midway between these two endpoints is a region where deposition and preservation of mud is the largest within the FMTZ. 2) Fluid mud deposits are poorly preserved in the deepest parts of channels, likely due to the high energy levels in this environment. Nevertheless, our results do not preclude the possibility that significant accumulations may occur in the shallow parts of the cross-channel profile. 3) Mud facies diversity is an indicator of depositional position along the FMTZ. Facies diversity was greatest at the middle observational site, which corresponds to the area that is subject to the most variable process regime. The landward and seaward ends of the transition zone exhibit a greater level of dominance in solely riverine or marine depositional processes, respectively. This study yields new insights into the process-response relationships for mud deposition at the interface of land to sea.

year: 2022

title: Rising demand for health care: The sustainability of community general practice in the Waikato

authors: Amey, Janet Heather

subjects: General practice

abstract: Community general practice is the cornerstone of New Zealand’s health system, providing first contact health care, care coordination and acting as gatekeeper to expensive hospital services. An ageing population now brings increasing demand for the care provided in general practice, with chronic conditions a major contributing factor. This rising demand, alongside limited workforce capacity will seriously test general practice sustainability. 

These evolving and multifaceted challenges are within the context of long-standing health access and outcome inequalities, particularly for Māori (and more recently the Pacific population) compared with Pākehā. The pursuit of equity is inherent in all health sector strategies, but any meaningful improvement will necessitate wide-ranging reform of current planning, funding and service delivery pathways across traditional sector boundaries.

The sustainability of general practice is about the sustainability and efficiency of the entire health system. To better measure the contribution of general practice care to the system, and improve demand projections, an expanded service use measure was developed, combining services of a general practice nature from Emergency Department and Accident & Medical settings with services delivered in community general practice.

Drawing on approaches from demography, epidemiology and health services research, linked demographic and health administrative data were used to undertake a retrospective, observational study of service use for 235,666 people enrolled with the Pinnacle Midlands Health Network in 2013/14. Using the new expanded measure, service use levels at a locality level were established by age, gender, ethnic group, chronic condition status, practice funding model, high needs status, income and geography of residence.

Significant variation was found in annual average consults (1.0 to 13.4 consults in 2013/14). Statistical analysis identified age, chronic conditions and gender as the key demand drivers responsible for such variation, with regional level results masking significant spatial variation. Where the cost of care was lower, people used a higher level of services in the enrolled practice setting and a lower level outside of it, suggesting the importance of affordable care. Māori and Pacific used significantly fewer services than Pākehā although there was substantial sub-regional variation. Using the expanded measure, the vast majority of care was delivered in the enrolled setting, including for those with chronic conditions.

Demand projections, based on the expanded measure of general practice, out to 2038 show the uneven geography of future demand due to disordered cohort flows and sub-regional population contexts. Overall, demand for services is projected to rise by 34 per cent to almost two million consults across the Waikato District Health Board catchment, with this driven predominantly by services for those aged 65+ years (or 45+ years in Hamilton City, Waikato and Waipa Districts).

Models of care are being transformed as general practices and Primary Health Organisations look to the future. Reorganisation of work roles, improved use of health information and use of emerging health technologies will be required to re-configure general practice in preparation for an ageing future, and to eliminate recalcitrant health inequalities. Real and inclusive collaboration across traditional system boundaries is perhaps the greatest challenge to general practice sustainability.

text: Rising demand for health care: The sustainability of community general practice in the Waikato Community general practice is the cornerstone of New Zealand’s health system, providing first contact health care, care coordination and acting as gatekeeper to expensive hospital services. An ageing population now brings increasing demand for the care provided in general practice, with chronic conditions a major contributing factor. This rising demand, alongside limited workforce capacity will seriously test general practice sustainability. 

These evolving and multifaceted challenges are within the context of long-standing health access and outcome inequalities, particularly for Māori (and more recently the Pacific population) compared with Pākehā. The pursuit of equity is inherent in all health sector strategies, but any meaningful improvement will necessitate wide-ranging reform of current planning, funding and service delivery pathways across traditional sector boundaries.

The sustainability of general practice is about the sustainability and efficiency of the entire health system. To better measure the contribution of general practice care to the system, and improve demand projections, an expanded service use measure was developed, combining services of a general practice nature from Emergency Department and Accident & Medical settings with services delivered in community general practice.

Drawing on approaches from demography, epidemiology and health services research, linked demographic and health administrative data were used to undertake a retrospective, observational study of service use for 235,666 people enrolled with the Pinnacle Midlands Health Network in 2013/14. Using the new expanded measure, service use levels at a locality level were established by age, gender, ethnic group, chronic condition status, practice funding model, high needs status, income and geography of residence.

Significant variation was found in annual average consults (1.0 to 13.4 consults in 2013/14). Statistical analysis identified age, chronic conditions and gender as the key demand drivers responsible for such variation, with regional level results masking significant spatial variation. Where the cost of care was lower, people used a higher level of services in the enrolled practice setting and a lower level outside of it, suggesting the importance of affordable care. Māori and Pacific used significantly fewer services than Pākehā although there was substantial sub-regional variation. Using the expanded measure, the vast majority of care was delivered in the enrolled setting, including for those with chronic conditions.

Demand projections, based on the expanded measure of general practice, out to 2038 show the uneven geography of future demand due to disordered cohort flows and sub-regional population contexts. Overall, demand for services is projected to rise by 34 per cent to almost two million consults across the Waikato District Health Board catchment, with this driven predominantly by services for those aged 65+ years (or 45+ years in Hamilton City, Waikato and Waipa Districts).

Models of care are being transformed as general practices and Primary Health Organisations look to the future. Reorganisation of work roles, improved use of health information and use of emerging health technologies will be required to re-configure general practice in preparation for an ageing future, and to eliminate recalcitrant health inequalities. Real and inclusive collaboration across traditional system boundaries is perhaps the greatest challenge to general practice sustainability.

year: 2018