Disability Weights For Health Damage From Cadmium Contamination Sites

Objective:Cadmium contamination sites are becoming more and more serious with the development of modern industrial processes,and studies have shown that the concentration of cadmium in soil and crops is increasing at a rate of 0.2% per year.Currently there is an increase in health damage litigation for environmental pollution and compensation for health damage only includes direct economic losses for health damage,indirect economic losses are not possible due to lack of appropriate standards.Disability-adjusted life year(DALY)is the total number of healthy life years lost from the onset of illness to death,and can fully evaluate the indirect economic burden of health damage.Disability weight(DW)is an important parameter to quantify DALY and is expressed as a number between 0 and1,with 0 indicating complete health and 1 indicating death.The health damage due to cadmium contamination sites is multi-organ and multi-system compound diseases with progressive nature and complexity of multiple health damages co-existing,which are not possible to achieve DW calculation by the current co-morbidity adjustment method in global burden of diseases(GBD)studies.Therefore,this study combines literature analysis and expert consultation method to clarify the health state description of health damage due to cadmium contamination sites,establish the DW calculation method of health state,and provide more data support from reasonable punitive damages in judicial proceedings of health damage of cadmium contaminated sites.Methods:The health state descriptions in this study consisted of three components: disease labels,professional descriptions,and functional impairment descriptions.The accuracy of the descriptions was clarified by combining literature analysis and expert consultation methods.A total of 13 health states were selected from 12 health states ranging from mild to severe and "deafness" to construct a matched control health state severity spectrum,which was combined with expert Delphi method to demonstrate its consistency with GBD2019 health states.A questionnaire survey was conducted using the paired comparison(PC)for the general community population and the health care professional population,with the general community population using a multi-stage stratified random sampling method and the health care professional population using a two-stage sampling method.The sample size of general community population and health care professional population was at least 480,respectively.The questionnaire survey was conducted from June 1,2022 to August 31,2022,and 454 valid questionnaires were collected from the general community population,with an effective rate of 82.25%,and 429 valid questionnaires were collected from the health care professional population,with an effective rate of 87.91%.The internal consistency results of the paired comparison questions were represented by heat maps,and the differences between different health states were quantified using probit regression to obtain the probability regression coefficients of the health states.The DW values of chronic cadmium poisoning were obtained by fitting the probability regression coefficients based on a local regression(LOESS)model,and the 95% uncertainty interval(UI)of the DW of the health states were estimated using a Monte Carlo model.The comparability of the DW of this study with the results of the GBD2019 study was assessed by Spearman correlation analysis.Results:Fifteen health state descriptions were obtained in this study,of which 12 health states in the health state study degree spectrum were considered consistent with the GBD2019 health state descriptions.In the general community population survey,with a minimum DW of 0.012(95% UI: 0.002-0.068)for mild visual impairment and a maximum DW of 0.573(95% UI: 0.206-0.873)for tetraplegia,including 0.097(95% UI: 0.049-0.183)for chronic mild cadmium poisoning and 0.364(95% UI: 0.196-0.183)for chronic severe cadmium poisoning with a DW of 0.364(95% UI: 0.196-0.572).In the health care professional population a,with a minimum DW of 0.012(95% UI: 0.002-0.066)for mild visual impairment and a maximum DW of 0.581(95% UI: 0.228-0.867)for tetraplegia,with a chronic mild cadmium poisoning DW was 0.102(95% UI: 0.052-0.189)and 0.397(95% UI: 0.215-0.611)for chronic severe cadmium poisoning.The general community population DW had a Spearman correlation coefficient of 0.644(P<0.05)with the GBD2019 study and 0.718(P<0.01)with the Chinese localized DW study,indicating an overall correlation.The health care professional population DW had a Spearman correlation coefficient of 0.669 with the GBD2019 study(P<0.05),the Spearman correlation coefficient with the Chinese localized DW study was 0.725(P<0.01),indicating an overall correlation.The Spearman correlation coefficient between the general community population and the health care professional population was 0.945(P<0.001),indicating an overall high correlation between the DW obtained from different populations.Conclusion:This study used the health state description consisting of disease labels,professional descriptions and functional impairment descriptions to obtain disability weights for 15 health states using the paired comparison introduced by the GBD with the general community population and the health care professional population as respondents.The DW of chronic mild cadmium poisoning in the general community population was0.097(95% UI: 0.049-0.183)and 0.364(95% UI: 0.196-0.572)for chronic severe cadmium poisoning.The DW of chronic mild cadmium poisoning in the health care professional population was 0.102(95% UI: 0.052-0.189),and DW for chronic severe cadmium severity was 0.397(95% UI: 0.215-0.611).The DWs of the general community population and the DWs of the health care professional population in this study were consistent.This study correlated with the DW study of GBD2019 and the localized DW study in China.This study expands the evidence base for GBD-based paired comparison method to derive DW studies and provides a reference for more litigation compensation for health damages caused by site contamination.