# Current Research and Statistical Practices in Sport Science and a Need for Change

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## Abstract

**:**

## 1. The Problem

## 2. The Solution

- (1)
- Defining the problem
- (2)
- Descriptive research (hypothesis generating)
- (3)
- Predictors of performance
- (4)
- Experimental testing of predictors
- (5)
- Determinants of key performance predictors
- (6)
- Efficacy studies (controlled laboratory or field)
- (7)
- Barriers to uptake
- (8)
- Implementation studies (real sporting setting)

## 3. Current Alternative Statistical Methods

#### 3.1. Smallest Worthwhile Change

_{z}), as there is no clear relationship between fitness-test performance and team performance [23]. The smallest worthwhile change is then equal to 0.2 of d [23].

#### 3.2. Comparing Correlations

#### 3.3. Effect Size

_{s}is calculated by using the pooled standard deviation of the groups and is used when investigating independent groups. When determining the effect in a one sample group, the standard deviation difference in scores can be used as the standardizer to calculate d

_{z}. When dealing with a small sample size and meta analyses, a Hedges’ g correction can be computed. Calculating Cohen’s d

_{s}based off sample averages may give a biased estimate of the population effect size, especially for samples under twenty participants [29]. Cohen’s d

_{s}can be converted to the adjusted Hedge’s g

_{s}by [28]:

#### 3.4. Confidence Intervals

#### 3.5. Magnitude-Based Inferences

#### 3.6. Counter-Argument against Magnitude-Based Inferences

## 4. Bayesian Estimation

## 5. Conclusions

## Supplementary Materials

## Author Contributions

## Conflicts of Interest

## References

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**MDPI and ACS Style**

Bernards, J.R.; Sato, K.; Haff, G.G.; Bazyler, C.D.
Current Research and Statistical Practices in Sport Science and a Need for Change. *Sports* **2017**, *5*, 87.
https://doi.org/10.3390/sports5040087

**AMA Style**

Bernards JR, Sato K, Haff GG, Bazyler CD.
Current Research and Statistical Practices in Sport Science and a Need for Change. *Sports*. 2017; 5(4):87.
https://doi.org/10.3390/sports5040087

**Chicago/Turabian Style**

Bernards, Jake R., Kimitake Sato, G. Gregory Haff, and Caleb D. Bazyler.
2017. "Current Research and Statistical Practices in Sport Science and a Need for Change" *Sports* 5, no. 4: 87.
https://doi.org/10.3390/sports5040087