McNickle v Huntsman Chemical Company Australia Pty Ltd

Introduction 309 It is not an overstatement to describe the AHS as a highly significant study. Much time was devoted to it in oral and written submissions and, as will become evident, the AHS constituted a study that Monsanto pointed to as being the single most important aspect of the evidence contrary to Mr McNickle's case. Despite this, at least initially, its reception into evidence was far from certain and the road to its adduction was a long and windy one. 310 As I noted in McNickle v Huntsman Chemical Company Australia Pty Ltd (Additional Expert Conclave) (at [1]), in December 2022, an interlocutory application was filed by Mr McNickle whereby permission was sought to communicate with Mr Cowpe, the independent barrister, who convened the expert conclaves (see above (at [24])) for the purpose of requesting that he facilitate the provision of a data transfer agreement, and the data underlying two epidemiology studies based on the AHS papers. As I noted (at [7]-[11]): [7] What emerged following Conclave D was that the main disagreement between the experts in analysing both De Roos and Andreotti relates to what is described as the "the correct allocation of person years and consequent calculation of rate ratios." It is Professor Gordon's opinion that the allocation of person years to levels of cumulative exposure to glyphosate was incorrectly carried out, and led to incorrect calculations of rate ratios. Dr Harris' opinion, however, was that the allocation of person years was correctly carried out, and led to accurate calculations of rate ratios. [8] Hence, the parties are at issue as to what Professor Gordon describes as a "serious analytic error". The consequence of this error is said to be that it could result in a "downward bias in the risk of NHL in the highest category of glyphosate exposure". It is said by Dr Harris that Professor Gordon has provided "no direct evidence of this error", and that this belief could only be substantiated "if the underlying AHS data were obtained and reanalysed". [9] No doubt I am missing something, but it seems to me it is a tad curious that the applicant, Mr McNickle, is the party seeking to obtain the AHS data. It is the respondents who seek to deploy opinions contained in articles from both Dr Roos and Andreotti in their case. If there is some prima facie, rational basis for suggesting that this material might have a serious analytical error, which can only be ascertained upon the checking of the underlying data, the failure to produce the data by the party seeking to adduce and rely upon the evidence, might have been relied upon to ground an application by the other party for rejection, or discretionary exclusion, or limitation of the material or, alternatively, support submissions going to the weight of the representations contained in the articles. But as it happens, both parties have reached a consensus that it is appropriate that the AHS data be obtained and reanalysed … [10] So far, so good. One would have thought this would be a relatively straightforward process of obtaining the data, providing it to the experts and obtaining their further opinions on it. But like so many matters in this case, it is not quite as simple as that. The AHS data is maintained by the National Cancer Institute (NCI), a United States government body that is part of the Department of Health and Human Services, being part of the executive government of the United States of America. For well over a year, efforts have been made by the solicitors for the applicant to obtain a copy of this data. [11] Remarkably, since August 2021, around 60 communications have been exchanged concerning the appropriate facilitation of the data to experts. I had indicated at a case management hearing in September 2022 that I was content for the parties to continue to make efforts to obtain material to be provided to the facilitator in the same way as other documents in order for the experts, if they thought the material relevant, to express their opinions as to the questions posed to them. What has become apparent, however, following communications by the solicitors for both parties and representatives of the NCI, is that the position of the NCI is as follows (as explained in the Affidavit of Mr Lee Taylor sworn 7 November 2022 (at [18])): (a) The NCI explained that the raw data are not contained in simple spreadsheets that are legible or reviewable by non-specialists. Rather, the data - which comprise the records of over 50,000 participants in the AHS - are raw text which can only be analysed within statistical software platforms. The NCI maintains the data in a software suite known as SAS (Statistical Analysis System) which, I understand, was developed in part by the National Institute of Health, of which the NCI is a part. Dr Beane-Freeman explained that they are able to export the data in a form that can be used in comparable analytic platforms (such as MATLAB). (b) Because the data are in the form described above, there would be no utility to providing the AHS Data in its raw form to the parties' lawyers or indeed to the Court. The data cannot be interpreted or "interrogated" by non-specialists without appropriate statistical qualifications, training, and experience, as well as the necessary statistical analysis software. To the extent, therefore, that the parties' lawyers need to challenge any expert's analysis of the AHS Data, they will likely need to rely on their own expert(s) (who will have the data). (c) The NCI's policy and practice of providing AHS Data to expert researchers is critical to their overarching mission as a public health body. The AHS Data comprise personal medical information of rural farmers enrolled in the AHS, and if the NCI is unable to guarantee that its subjects' privacy is fully protected, the integrity of the AHS (and similar projects) would be fundamentally at risk. That imperative is served by providing data only to experts in relevant fields who are properly trained in managing and using health data, and who are experienced in deploying that data in a manner consistent with the privacy requirements (such as in publications using the data), and whose institutions typically use such data and therefore have appropriate systems in place to manage and protect the data. (d) The NCI is aware that the AHS Data are sought in connection with this proceeding and that they would be used by expert witnesses. (e) The Proposed DTA does not restrict the experts or the parties from using the experts' analyses of the data (as distinct from the raw data themselves) in open court, nor would it preclude those analyses being incorporated into the Court's analysis. (f) Under the Proposed DTA, the lawyers and/or the Court can request the experts to generate data outputs from the raw AHS Data. There is no restriction on how many or what type of outputs can be generated by the experts, other than that those outputs cannot be based on fewer than five individual study participants (of over 50,000). This is to ensure that study participants' privacy is protected. A data output is generated by aggregating the raw data of individual AHS participants to allow this data to be analysed and studied under different circumstances. Data outputs would reflect the results of particular analytic queries or calculations performed on the raw data; for example, the number of AHS participants were exposed to glyphosate in a particular year, might be extracted and then rendered in a form that would be intelligible to laypersons, such as a graph or chart, a table, or a textual description. Similarly, more complex outputs might be generated such as a re-calculation of participants' intensity-weighted cumulative lifetime days exposure (which is a focus of Professor Gordon's analysis), which would also be rendered in a form intelligible to the parties' legal representatives and the Court. (g) These outputs will enable the data to be digested and analysed so that the parties' lawyers and the Court can properly understand what the data show. These outputs from the raw data can be used by the parties' lawyers or the Court to test the experts' opinions, methodology and analyses. The outputs from the raw AHS Data can be referred to in open court. (h) The lawyers and the Court would then be able to ask the experts questions regarding their analyses, opinions and methodology, including based upon any outputs generated by the experts from the raw AHS Data. 311 As I then explained (at [19]-[25]), I facilitated an arrangement agreed between the parties for material to be provided by the NCI to the two experts in Conclave D. 312 Without access being obtained to the underlying data so that the conclusions of the AHS could be tested, it would have at least been open to Mr McNickle to move for the discretionary exclusion of opinions based on the AHS, as the refusal of the NCI to produce those materials would have occasioned prejudice to Mr McNickle in seeking to challenge the conclusions drawn from the AHS. But this was not the forensic course adopted by Mr McNickle and a pragmatic solution was reached in order to allow this important material to be placed before the Court. 313 Returning to the AHS itself, the study is a prospective cohort study conducted in Iowa and North Carolina. It includes 57,311 private and commercial licensed pesticide applicators, who were recruited between 1993 and 1997. Among private and commercial applicators, 75.5% (or approximately 43,000 people) reported ever using glyphosate. Exposures to glyphosate and other pesticides were assessed from responses to self-administered questionnaires completed by study participants. 314 Two studies (that is, the AHS papers) are follow-up reports on the AHS, namely: (1) De Roos A J, Blair A, Rusiecki JA, et al. (2005) "Cancer incidence among glyphosate-exposed pesticide applicators in the Agricultural Health Study" 113 Environ Health Perspect 49 (De Roos (2005)); and (2) Andreotti G, Koutros S, Hofmann J N, et al. (2018) "Glyphosate use and cancer incidence in the Agricultural Health Study" 110 J Natl Cancer Inst 509 (Andreotti (2018)). 315 For this reason, and partly because of the way in which Mr McNickle developed his arguments with respect to its findings, I will deal with it in a slightly modified sequence. 316 First, I will outline, at a high level, the conclusions of the AHS papers. Secondly, I will deal with Mr McNickle's contentions made in the context of Conclave D with respect to the reliability of the AHS papers. Thirdly, I will set out what I consider to be the key strengths of the AHS and make findings as to the weight to be attributed to it in the light of the above.