Given a nonresponse, we sent a reminder after 1 week.ResultsThe PsycINFO database contained 88,180 psychology articles that were published in 2008 in a peer-reviewed journal. There are no other cases in which Wicherts et al. The selection discrepancies consisted of three wrongly included regression F test and nine values reported in a table. As different people may have contributed to different studies, the questions would have been difficult or even impossible to answer if they had pertained to all studies. http://supercgis.com/how-to/reporting-standard-error-apa.html
Provo, Utah, USA. 31. Furthermore, an independent rater, who was blind to the aims of the study, identified and copied 256 statistical results from ten articles randomly chosen from our sample. Table 6 explains these inconsistencies in detail. The absolute mean difference in Cohen’s d due to misreporting was 0.169 (median = 0.065, SD = 0.211).
Surveys Is the Subject Area "Surveys" applicable to this article? Based on the study of Wicherts, Bakker, and Molenaar  who found a relationship between willingness to share research data and the prevalence of reporting errors in a sample of 48 did not, were results in which the p-value was reported to be zero (p = .000). Adding a fixed effect of significant/nonsignificant results at the statistics level did not improve model fit (AIC = 948.5; BIC = 968.7; LogLik = –470.2), χ²(1) = 0.02, p = .886, which means that
Inter-rater reliability was high: in most cases, both coders agreed on whether the study belonged to Study 1 (Cohen’s Kappa = 0.92) and on whether the results were reported as one-sided or as Following that, report the t statistic (rounded to two decimal places) and the significance level. Psychological Science. 35. How To Write Descriptive Statistics Results The probability that a p-value in the first (or only) study reported comprises a gross error: co-piloted studies versus non-co-piloted studies.Note.
In line with earlier research, we found that half of all published psychology papers that use NHST contained at least one p-value that was inconsistent with its test statistic and degrees Statistical Report Example Similar yet slightly lower error rates have been found in the medical literature ,  and in recent replications , , . Furthermore, whereas JPSP was the journal with the highest percentage of articles with inconsistencies, it had one of the lowest probabilities that a p-value in an article was inconsistent (9.0 %). http://my.ilstu.edu/~jhkahn/apastats.html Even though the percentage of results that is grossly inconsistent is lower, the studies show that a substantial percentage of published articles contain at least one gross inconsistency, which is reason
However, the results of the analyses as written down in the manuscript were checked by a second person slightly more often than not (54.9%, CI [49.5%−60.2%). doi: 10.1037//0003-066x.49.12.997 View Article PubMed/NCBI Google Scholar 2. Reporting Descriptive Statistics Apa Not all studies will require sample size calculations: for example, pilot or small-scale feasibility studies which are the first assessment of a treatment in a particular setting and are used to How To Report Mean And Standard Deviation Our estimate of the probability that a p-value comprises an error was in between the estimates of Bakker and Wicherts: 10% vs 7%  and 18% ).
Wicherts et al. check my blog Journal of Abnormal and Social Psychology. 1962;65:145–153. The second study involved a fully random sample of articles published in 2008 in peer-reviewed psychology journals, and although the sample of articles may not be large, our results are based Computed tomography findings in liver fibrosis and cirrhosis Cochlear implantation in children and adults in Switzerland Windswept lower limb deformities in patients with hypophosphataemic rickets Latest comments janexhibition on Nanotechnology in How To Report Descriptive Statistics
The fact that we asked respondents to indicate which authors were involved in each part of the processes rather than asking how many people were involved may have also rendered the Peter Suter, Geneva (senior editor) Supported by The "Swiss Medical Weekly" is supported by the Swiss Academy of Medical Sciences (SAMS) and the Swiss Medical Association (FMH). Cohen J (1994) The earth is round (P less-than.05). http://supercgis.com/how-to/reporting-mean-square-error-in-anova.html This suggests that copy–paste errors are quite common.
Cronin B, Shaw D, La Barre K (2003) A cast of thousands: Coauthorship and subauthorship collaboration in the 20th century as manifested in the scholarly journal literature of psychology and philosophy. Statistical Report Template American Psychologist 38:414–423. We simply do not know whether the test statistic, the df, and/or the p value were misreported.
The inter-rater reliability for decision errors was somewhat lower (Cohen’s Kappa = 0.77), because of possible disagreement on whether the result was tested as one-sided or as two-sided due to ambiguous reporting. low) at the journal level as a fixed effect. Although we cannot interpret the absolute percentages and their differences, the finding that gross inconsistencies are more likely in p-values presented as significant than in p-values presented as nonsignificant could indicate Statistical Report Example Model Theory & Psychology. 2000;10:413–425.
PLoS ONE. 17. Veldkamp ([email protected]) or Jelte M. Of these differences, 18% can be classified as small (i.e., less than .01), but 41% were substantial (i.e., greater than .10). http://supercgis.com/how-to/reporting-anova-mean-square-error.html Note that in 1985 the APA manual already required statistics to be reported in the manner that statcheck can read (American Psychological Association, 1983).
Nevertheless, even with access to the raw data, the causes of some errors remained unknown. The total number of statistical results and the number of errors per significance category are reported in Table 5. The errors with respect to exactly reported p values were classified as follows: Incomplete: test statistic, df, or p value missing.Rounding errors: wrongly rounded upward or downward. The correct rounding of test statistics is not incorporated in the automatic one-tailed test detection, but this will be incorporated in the next version.
The selection of statistical results was consistent in 95.4% of the cases, and the copying of the statistical results was consistent in 99.6% of the cases. Although the use and interpretation of this method have been criticized (e.g. , , ), it continues to be the main method of statistical inference in psychological research , . Loading metrics Open Access Peer-reviewed Research Article Statistical Reporting Errors and Collaboration on Statistical Analyses in Psychological Science Coosje L. Thirty-five percent of the articles contained at least one error.
It is possible that in some cases a nonsignificant p-value would be in line with a hypothesis and thus in line with the researcher’s predictions. vs. 9.0 % or 7.2 % of all results in statcheck, without or with one-tailed detection, respectively). A possible explanation for the difference with the higher estimate of 18%  is that in the first study by Bakker and Wicherts , statistical results that were not exactly reported This discrepancy is caused by a difference between journals in the number of p-values per article: the articles in JPSP contain many p-values (see Table 1, right column).
However, if the data are stored on one researcher’s hard drive, the risk of loss of the data is considerable. Notwithstanding these criticisms, NHST remains the most commonly used method of statistical testing in psychology (Cumming et al., 2007). were due to seven one-tailed tests (see Table 7). The last two questions in this set pertained to data sharing and asked how many people (5) had access to the data when the manuscript was submitted, and (6) currently have
Table 2 shows the prevalence of inconsistent p-values as determined by our study and previous studies.Table 2Prevalence of inconsistencies in the current study and in earlier studiesStudyFieldNo. The first example below shows a comparison of three means. Researchers often have specific preferences regarding their results, which may affect the extent to which researchers scrutinize errors in line with or contradicting their preferred results. Many of the unselected articles contained other statistical analyses (e.g., regression analysis, structural equation modelling, nonparametric tests), while 29 articles (17%) reported only p values.