Zapf et al. BMC Medical Research Methodology (2020) 20:23 https://doi.org/10.1186/s12874-020-0916-4 DEBATE Open Access Why do you need a biostatistician? Antonia Zapf1* , Geraldine Rauch2 and Meinhard Kieser3 Abstract The quality of medical research importantly depends, among other aspects, on a valid statistical planning of the study, analysis of the data, and reporting of the results, which is usually guaranteed by a biostatistician. However, there are several related professions next to the biostatistician, for example epidemiologists, medical informaticians and bioinformaticians. For medical experts, it is often not clear what the differences between these professions are and how the specific role of a biostatistician can be described. For physicians involved in medical research, this is problematic because false expectations often lead to frustration on both sides. Therefore, the aim of this article is to outline the tasks and responsibilities of biostatisticians in clinical trials as well as in other fields of application in medical research. Keywords: Medical research, Biostatistician, Tasks, Responsibilities Background Biometric Society (IBS) provides a definition of biomet- What is a biostatistician, what does he or she actually do rics as a ‘field of development of statistical and mathem- and what distinguishes him or her from, for example, an atical methods applicable in the biological sciences’ [2]. epidemiologist? If we would ask this our main cooper- In here, we will focus on (human) medicine as area of ation partners like physicians or biologists, they probably application, but the results can be easily transferred to could not give a satisfying answer. This is problematic the other biological sciences like, for example, agricul- because false expectations often lead to frustration on ture or ecology. As mentioned above, there are some both sides. Therefore, in this article we want to clarify professions neighbouring biostatistics, and for many co- the tasks and responsibilities of biostatisticians. operation partners, the differences between biostatisti- There are some expressions which are often used cians, medical informaticians, bioinformaticians, and interchangeably to the term ‘biostatistician’. In here, we epidemiologists are not clear. According to the current will use the expression ‘(medical) biostatistics’ as a syno- representatives of these four disciplines within the Ger- nym for ‘medical biometry’ and ‘medical statistics’, and man Association for Medical Informatics, Biometry and analogously we will do for the term ‘biostatistician’. Epidemiology (GMDS) e. V.: In contrast to the clearly defined educational and pro- fessional career steps of a physician, there is no unique ‘Medical biostatistics develops, implements, and uses way of becoming a biostatistician. Only very few univer- statistical and mathematical methods to allow for a sities do indeed offer studies in biometry, which is why gain of knowledge from medical data.’‘Results are most people working as biostatisticians studied some- made accessible for the individual medical thing related, subjects such as mathematics or statistics, disciplines and for the public by statistically valid or application subjects such as medicine, psychology, or interpretations and suitable presentations’ (authors’ biology. So a biostatistician cannot be defined by his or translation from [3]). her education, but must be defined by his or her expert- ‘Medical informatics is the science of the systematic ise and competencies [1]. This corresponds to our defin- development, management, storage, processing, and ition of a biostatistician in this article. The International provision of data, information and knowledge in medicine and healthcare’ (authors’ translation from [4]). Bioinformatics is a science for ‘the research, * Correspondence: [email protected] development and application of computer-based 1Department of Medical Biometry and Epidemiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany methods used to answer biomolecular and Full list of author information is available at the end of the article © The Author(s). 2020 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Zapf et al. BMC Medical Research Methodology (2020) 20:23 Page 2 of 6 biomedical research questions. Bioinformatics from the International Council for Harmonisation of mainly focusses on models and algorithms for data Technical Requirements for Pharmaceuticals for Human on the molecular and cell-biological level’ [5]. Use (ICH) explicitly states that statistical expertise ‘Epidemiology deals with the spread and the course should be utilized throughout all stages [8]. In there, it is of diseases and the underlying factors in the public. stated in Section 5.4.1: ‘The sponsor should utilize quali- Apart from conducting research into the causes of fied individuals (e.g. biostatisticians, clinical pharmacolo- disease, epidemiology also investigates options of gists, and physicians) as appropriate, throughout all prevention’ (authors’ translation from [6]). stages of the trial process, from designing the protocol and CRFs [case report forms, AZ] and planning the ana- Another discipline is data science, which is a relatively lyses to analyzing and preparing interim and final clin- new expression used in a multitude of different contexts. ical trial reports.’ Mansmann et al. [9] provided a more Often it is meant as a global summarizing term covering specific guidance about good biometrical practice in all of the above mentioned fields. As there is no com- medical research and the responsibilities of a biostatisti- mon agreement on what data science is and as this term cian. In there, the responsibility of a biostatistician is de- does not correspond to a uniquely defined profession, scribed as a person participating in the planning and the this expression will not be discussed in more detail. execution of a study, in the dissemination of the results The self-descriptions as stated above are rather general and in statistical refereeing. These are very general and not necessarily complete. Therefore, we will in the descriptions of the tasks and responsibilities of biostatis- following describe the specific tasks and responsibilities ticians. In the following, we will explain the biostatisti- of biostatisticians in different important application cian’s mission in more detail based on the guidance on fields in more detail. This allows us to specify what co- good biometrical practice [9] and on the E9 guideline operation partners may (or may not) expect from a bio- from the ICH about Statistical Principles for Clinical statistician. Furthermore, clarification of the roles of all Trials [10]. involved parties and their successful implementation in In the initial phase of a medical research project, a bio- practice will overall lead to more efficient collaborations statistician should actively participate in the assessment and higher quality. of the relevance and the feasibility of the study. During the planning phase, the biostatistician should already be Main text involved in the discussion of general study aspects as Tasks and responsibilities of biostatisticians outlined in more detail below. It is evident that the phys- There are many medical areas where biostatisticians can ician must provide the framework for this. However, the contribute to the general research progress. These fields biostatistician can and should point out important bio- of application and the related biostatistical methods are statistical issues which will have important influence on not strictly separated, but there are many overlaps and a the whole construct of the study. Therefore, an import- classification of the related methodology can be done in ant part of the biostatistician’s work is to be done long various ways. We consider in the following the import- before a study can start. For example, the appropriate ant application fields of clinical trials, systematic reviews study population (special subgroups or healthy subjects and meta-analysis, observational and complex interven- in early phases versus large representative samples of the tional studies, and statistical genetics to highlight the targeted patient population in confirmatory trials) and tasks and responsibilities of biostatisticians working in reasonable primary and secondary endpoints (e.g. suit- these areas. able to the study aim, objectively measurable, clearly and uniquely defined) need to be identified. He also should Biostatisticians working in the area of clinical trials make the physician aware of the potential problems with The tasks of biostatisticians in clinical trials are not lim- multiple or composite primary endpoints and with sur- ited to the analysis of the data, but there are many more rogate or categorised (especially dichotomized) variables. responsibilities. It is a quite misguided view that biostat- Another very important topic related to the general isticians are only