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-balck people and white people are different.
The latest This Week in Blackness is titled “Black People and White People Are Different.” It’s based on the popular style of jokes that permeated the ’90s in comedy clubs across the country. You’ve probably heard some form of joke like, “White people talk like this, black people talk like that.” The interesting thing about the video title is that some people will become enraged and yell, “Ugh, you’re highlighting and promoting differences between races and this will do nothing more than to continue to heighten the tensions that already exist!” Others will respond with an emotionally flat, “Duh.” A weird byproduct of the post-racialization of America is the desire that some have to stomp out anything that sticks out as “other” between the races. When one points out differences in treatment or experiences (like I do, regularly) they’re immediately attacked and called a bigot or racist (like, well, here on this site, for example).
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 The results of a systematic review of a health care intervention are liable to be influenced by systematic error (bias), as is the case with any observational study. There is a risk of bias influencing a review if the characteristics of, and distribution of reports (concerning a particular treatment) within and outside the medical literature are associated with the nature and direction (degree of harm or benefit, statistical significance, precision) of the results. In other words, there is a risk of bias at the secondary level if account is not taken of bias in the primary research literature. Any action taken by the reviewer should be appropriate to the type of bias and could involve, for example, a careful search for trials from a certain source, or the exclusion of trials from a certain chronological period, or a cautious appraisal of results selectively reported by trialists. DefinitionsThe characteristics of reports include the outcome estimator used (e.g. Odds Ratio), the primary outcome selected by the investigator (e.g. freedom from symptoms, death) and the sub-group results actually appearing in the report (e.g. patient status after three months, patients under 40 years of age). The distributions of reports relates, for example, to the differential publication and non-publication of reports according to their results, to the accessibility of reports (e.g. their appearance in some databases and not in others), and to the appearance of reports in English language journals or in languages other than English in a pattern that is related to their results. Types of Bias Bias has the potential to affect reviews of both experimental and observational studies. Some of the different types of bias are summarized below. However, work-to-date has focused mainly on the reports of trials and the potential impact of bias on meta-analyses of trials. A prime example is "publication bias", an issue in social science research for over forty years (Sterling 1959; Smith 1980). There is now considerable evidence that trials which are not formally published ("grey trials"), and have to be accessed from sources such as conference reports or contact with trialists, have results that differ systematically (showing less benefit of treatment) from those published in journals (Simes 1986; Dickersin 1990, Easterbrook 1991; Dickersin 1997; McAuley et al. 2000; Bartlett et al. 2000; Pham B 2000; Sterne et al. 2000; Sutton et al. 2000). Trials with less beneficial results, moreover, tend to take longer to achieve publication than trials with more optimistic results ("time lag bias") (Stern and Simes 1997; Clarke and Hopewell 2000). Many reviewers endeavour to avoid publication bias by attempting to identify and include all relevant trials from the grey literature. However, this is a time-consuming process and estimates of the average impact of the grey literature have varied in magnitude. Further investigation is required if pragmatic guidelines for reviewers are to be drawn up. Forms of bias are also connected with the following: language of journals ("language bias") (Gregoire et al. 1995; Moher et al. 1996; Egger et al. 1997; Moher et al. 2000; Jüni et al. 2000); with the source of funding for the primary research ("funding bias") (Davidson 1986; Rochon et al. 1994; Cho and Bero 1996); with the selective reporting of results within primary studies ("outcome variable selection bias") (Hutton and Williamson 2000; Hahn et al. 2000; Hahn, Williamson and Hutton 2002) (also known as "within-study reporting bias"); with the inclusion of reports within some bibliographic databases and not within others ("database bias") (Zielinski 1995); with inconsistent coding within databases ("coding bias"); and preferential citation of certain results by scientific authors ("citation bias"). These last three biases are also sometimes referred to as "retrieval biases" and a case might be made for regarding them as constituting a class of bias distinct from other types of reporting bias. The nature of the results and outcome of a study may also be associated with the geographical location in which the study was undertaken or in which the researchers were based (Vickers et al. 1998; Pittler et al. 2000). For example, it may also be more difficult for studies from some regions, most notably developing countries, to achieve full publication or publication in the most accessible journals (Zielinski 1995; Wayt Gibbs 1995). "Regional Bias" and "Developed Country Biases" may affect the results of some systematic reviews and meta-analyses, and have significant consequences for the practice of evidence-based health care around the world, particularly in developing countries. Complicating Factors Additional considerations for the reviewer are the questions of whether bias and its impact varies by topic area, for example, by medical specialty, by type of intervention (e.g. drug or non-drug), or according to whether the intervention is complementary or conventional medicine, or according to the subject population (e.g. children or adults). There is also the issue of whether a bias in primary studies is inevitably associated with lack of quality. The level of quality of primary research, (the level of bias in the design and conduct of primary studies) is a major issue for Cochrane reviewers, and investigations into bias will, of necessity, involve consideration of the quality of primary studies. Observational Studies and Reviews without Large Meta-analyses With regard to observational studies, our knowledge of the pattern of bias and its potential impact on meta-analyses is markedly more limited than is the case with trials. Knowledge is also very limited with regard to the influence of bias on systematic reviews without meta-analyses and on meta-analyses likely to contain a small number of trials. Reviewer Bias The BMG is concerned with the way factors relating to the results of primary studies might lead to bias at the secondary level, that is, in a systematic review. However, the BMG will also investigate "Reviewer Bias" (Ernst 1994; Cates 1998), subjective bias introduced by the systematic reviewer at the level of secondary research, in a way that cannot be wholly attributed to the characteristics of the primary studies. This consideration might be made because some of the methodological approaches used would be similar to those used for investigating primary reporting bias and it is possible that reviewer bias could compound the effects of the reporting biases. Types of Reporting Bias & Definitions
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