title: Statistical aspects of environmental risk assessment of GM plants for effects on non-target organisms.
abstract: Previous European guidance for environmental risk assessment of genetically modified plants emphasized the concepts of statistical power but provided no explicit requirements for the provision of statistical power analyses. Similarly, whilst the need for good experimental designs was stressed, no minimum guidelines were set for replication or sample sizes. Furthermore, although substantial equivalence was stressed as central to risk assessment, no means of quantification of this concept was given. This paper suggests several ways in which existing guidance might be revised to address these problems. One approach explored is the ;bioequivalence' test, which has the advantage that the error of most concern to the consumer may be set relatively easily. Also, since the burden of proof is placed on the experimenter, the test promotes high-quality, well-replicated experiments with sufficient statistical power. Other recommendations cover the specification of effect sizes, the choice of appropriate comparators, the use of positive controls, meta-analyses, multivariate analysis and diversity indices. Specific guidance is suggested for experimental designs of field trials and their statistical analyses. A checklist for experimental design is proposed to accompany all environmental risk assessments.
authors.affiliation: Oaklands Barn, Lug's Lane, Broome, Norfolk, UK. joe.perry@bbsrc.ac.uk
authors.forename: Joe N
authors.initials: JN
authors.lastname: Perry
authors.forename: Cajo J F
authors.initials: CJ
authors.lastname: Ter Braak
authors.forename: Philip M
authors.initials: PM
authors.lastname: Dixon
authors.forename: Jian J
authors.initials: JJ
authors.lastname: Duan
authors.forename: Rosie S
authors.initials: RS
authors.lastname: Hails
authors.forename: Alexandra
authors.initials: A
authors.lastname: Huesken
authors.forename: Marc
authors.initials: M
authors.lastname: Lavielle
authors.forename: Michelle
authors.initials: M
authors.lastname: Marvier
authors.forename: Michele
authors.initials: M
authors.lastname: Scardi
authors.forename: Kerstin
authors.initials: K
authors.lastname: Schmidt
authors.forename: Bela
authors.initials: B
authors.lastname: Tothmeresz
authors.forename: Frank
authors.initials: F
authors.lastname: Schaarschmidt
authors.forename: Hilko
authors.initials: H
authors.lastname: van der Voet
mesh_terms: D000821:Animal Feed; D000818:Animals; D003257:Consumer Product Safety; D004784:Environmental Monitoring; D005511:Food Handling / Q000379:methods; D006801:Humans; D015233:Models, Statistical; D009753:Nutritive Value; D010571:Pest Control / Q000379:methods*; D030821:Plants, Genetically Modified; D011358:Product Surveillance, Postmarketing; D018570:Risk Assessment; D018675:Toxicity Tests