Issues with using only regression models for ecotoxicity studies

Green, John W.

doi:10.1002/ieam.1723

Cited by 9 publications

(21 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The p value in Table confirms that this single data point has accounted for a significant change in the residual sum of squares. The NEC estimated using the model fitted to the reduced data set is 0.41 g/ha, which is very close to Green's EC10 of 0.39 g/ha, although our own estimate of the EC10, using a 4‐parameter log‐logistic function (resulting in a fitted curve similar to that reported by Green ), was 0.59 g/ha.…”

Section: A Reanalysis Of Green's Vegetative Vigor Study Datasupporting

confidence: 77%

“…One of the claimed benefits of the NOEC is that it can be computed in instances where a suitable (regression) model does not exist . As we have argued previously ( The No Observed Effect Concentration Fallacy ), this assertion is simply not true; and as our analysis of the data in Figure shows, there are times when the converse is true.…”

Section: A Regression Model For Histopathological Severity Scoresmentioning

confidence: 78%

“…Dry weight of oat plants example used in Green . Solid black points are data with possible outlier identified (solid red square); red curve is 4‐parameter no‐effect concentration (NEC) model fitted using all data (model 1); blue curve is 4‐parameter NEC model fitted with possible outlier removed (model 2); green curve is 4‐parameter log‐logistic function (model 3) fitted using all data.…”

Section: A Reanalysis Of Green's Vegetative Vigor Study Datamentioning

confidence: 99%

“…The present review continues our rebuttal of the NOEC approach [3]. We include a detailed rebuttal to Green [1] and include a worked example of an alternative method. A new regression method is presented for the analysis of severity scores.…”

mentioning

confidence: 94%

“…As we have pointed out in such cases, the only meaningful descriptor of the concentrationresponse relationship is the mean response taken over all measured concentrations [3]. Green and his collaborators' repeated claims that, in effect, the NOEC can somehow overcome the aforementioned problems resulting from either a poorly designed concentration-response experiment or an observation on the reality of a nonexistent response are not convincing [1,2,4].…”

mentioning

confidence: 99%

See 4 more Smart Citations

Don't be fooled—A no‐observed‐effect concentration is no substitute for a poor concentration–response experiment

Fox

Landis

2016

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

Renowned mathematician and science historian Jacob Bronowski once defined science as "the acceptance of what works and the rejection of what does not" and noted "that needs more courage than we might think." Such would also seem to be the case with noobserved-effect concentrations (NOECs) and no-observed-effect levels in ecotoxicology. Compelling arguments were advanced more than a quarter of a century ago as to why the use of a model to describe the concentration-response relationship was preferable to an isolated metric, with the NOEC singled out as a particularly poor toxicity measure. In the ensuing years numerous articles critical of the NOEC have been written, with some calling for an outright ban on its use. More recently, arguments have been made for the retention of NOECs, with supporters suggesting that this metric is particularly useful in situations where the concentration-response relationship is weak or nonexistent. In addition, it has been claimed that there are situations in ecotoxicology where suitable models are simply not available. These arguments are not correct, and they also have impeded the decades-overdue incorporation of numerous recommendations based on research that NOECs should no longer be used. In the present study the authors counter some of the most recent claims in support of NOECs and provide new insights for 1 class of problem claimed not to be amenable to such modeling. They are confident that similar insights will be developed as further original research in this area is undertaken. THE NO-OBSERVED-EFFECT CONCENTRATION FALLACYIn his recent learned discourse [1], Green continues to assert that the no-observed-effect concentration (NOEC) is a legitimate toxicity metric worthy of continued use by ecotoxicologists, particularly when dealing with "problematic" data such as those for which either "the concentration-response . . . shape is very shallow," "the control response is highly variable," or the "response has no pattern at all except at the highest 1 or 2 concentrations" [2]. Green suggests that in such cases "there might be no basis for proposing a model" [2], arguing instead that analysis of variance (ANOVA) techniques be used to generate the now widely discredited NOEC. As we have pointed out in such cases, the only meaningful descriptor of the concentrationresponse relationship is the mean response taken over all measured concentrations [3]. Green and his collaborators' repeated claims that, in effect, the NOEC can somehow overcome the aforementioned problems resulting from either a poorly designed concentration-response experiment or an observation on the reality of a nonexistent response are not convincing [1,2,4].The most recent contribution by Green perpetuates this assertion by stating "the NOEC often provides good information when no sound regression model exists" [1]. There is a logical inconsistency with this claim: if there is no response as a function of varying concentration, then there is no point at which the response changes and hence no concent...

show abstract

Section: A Reanalysis Of Green's Vegetative Vigor Study Datasupporting

confidence: 77%

Section: A Regression Model For Histopathological Severity Scoresmentioning

confidence: 78%

Section: A Reanalysis Of Green's Vegetative Vigor Study Datamentioning

confidence: 99%

mentioning

confidence: 94%

mentioning

confidence: 99%

See 3 more Smart Citations