Writing a paper, presenting results and data – day 1: presenting numerical values and statistics
Free PreviewNumbers and statistics
Numbers and statistics are always best represented through tables and figures, it is easier that trying to assimilate numbers and data through many entries in the text. The daily journal entries this week will help you to do that. It will also help you to describe the data in the tables.
The table below gives you the English version of the most common statistical phrases and words that you are likely to need.
Table 1: Common words in statistics and their meanings
Word | Meaning |
Analysis of Variance (ANOVA) | Tells you if there are any statistical differences between the means of three or more independent groups |
Coefficient | The multiplication factor and is written before the number it multiplies |
Correlation | Measure that expresses the extent to which two variables are linearly related |
Confounded | Variables whose effects cannot be distinguished |
Mean | The sum of all the values divided by the number of values, a type of average |
Mode | The most frequent value, a type of average |
Median | The middle value, a type of average |
Parameter | A numerical measure that describes a characteristic of a population |
p-value | The level of marginal significance within a statistical hypothesis test |
Population | All the members of the group that the study is about |
Power | The detection of a significant effect |
Regression | Predicting one variable based on the values of the other variables |
Samples | The parts of the population selected for analysis |
Standard deviation | Measure of the amount of variation or dispersion of a set of values |
t-test | A statistical test that is used to compare the means of two groups |
Variables | A characteristic of an item or an individual that will be analyzed using statistics |
The table below gives you a description of the most common statistical analyses that scientists use across many fields of science. You will be familiar with the main statistical analyses used in your field.
Table 2: Commonly used statistical analyses in science
Test | Type | Meaning |
Simple linear regression | Regression | How one variable can predict another |
Multiple linear regression | Regression | How two or more variables can predict another |
Paired t-test | Comparison | Comparing how two different variables can affect the outcome |
ANOVA | Comparison | Comparing how three or more variables can affect an average outcome |
Pearson’s r correlation | Correlation | Measuring how 2 continuous variables are related |
Useful words and phrases
Have a read through the results section below including the tables to see how these authors have structured their results. Afterwards we will look at their phrases for describing the results.
Results
This study included 26 patients with a mean age of 55 years (range: 44–88 years). The mean follow-up duration was 6.2 months. Table 1 summarizes all other characteristics. Among DFU patients, the NPWT group included 14 flaps (six free flaps and eight perforator flaps), and the conventional monitoring group included 12 flaps (five free flaps and seven perforator flaps). The mean flap surface area was 88.6 cm^{2}, and the mean operation time was 296.5 min (284.9 min in the NPWT group vs. 303.8 min in the conventional group; this difference was not statistically significant). All flaps were anterolateral thigh flaps.
Table 1 Demographic findings of the patients
Criteria | Conventional group | NPWT group | P-value |
Patient numbers | 12 | 14 | |
Age, y (range) | 53.8 (45–88) | 55.6 (44–84) | 0.84 |
Body mass index, kg/m^{2} (range) | 25.9 (17–32) | 24.7 (20.8–28.9) | 0.71 |
Type of flaps | 0.53 | ||
Free flap | 5 | 6 | |
Perforator flap | 7 | 8 | |
Hypertension | 0.64 | ||
Yes | 5 | 5 | |
No | 7 | 9 | |
Smoking | 0.61 | ||
Yes | 6 | 8 | |
No | 6 | 6 | |
Cardiovascular disease | 0.82 | ||
Yes | 4 | 3 | |
No | 8 | 11 |
- NPWT: negative pressure wound therapy.
There was no significant intergroup difference in flap survival rate (92.9% in the NPWT group vs. 91.7% in the conventional group, p = 0.83) (Table 2). In addition, there was no significant intergroup difference in the diameters of perforators or anastomosed vessels before and after NPWT (2.3 mm before NPWT application vs. 2.4 mm after NPWT application, p = 0.97).
Table 2 Surgical outcomes of conventional monitoring and NPWT monitoring groups.
Conventional group | NPWT group | P-value | |
Total number of flaps | 12 | 14 | |
Mean flap size (cm^{2}) | 87.8 ± 49.1 | 94.2 ± 41.7 | 0.45 |
Mean operation time (min) | 284.9 ± 65.7 | 303.8 ± 38.1 | 0.61 |
Flap survival | 11 | 13 | 0.83 |
Total Monitoring time*(min) | 86.4 | 225.1 | |
Flap complication | 3 | 1 | |
Infection | 2 | – | |
Hematoma | – | – | |
Seroma | – | – | |
Partial necrosis | – | – | |
Complete necrosis | 1 | 1 |
- NPWT: negative pressure wound therapy.
- *Total monitoring time: up to postoperative day 5.
Extract is taken from: Park, J.H., Park, JU. Flap monitoring with incisional negative pressure wound therapy (NPWT) in diabetic foot patients. Sci Rep 12, 15684 (2022). https://doi.org/10.1038/s41598-022-20088-9
In this short piece of text there were several useful phrases for describing results and making comparisons.
This study included: used to inform the reader about the sample size
a mean age of 55 years: tells you an average of one of the characteristics of the sample
mean follow-up duration: gives the reader the average time frame for the measured study
summarizes all other characteristics: telling the reader that all of the variables are detailed
this difference was not statistically significant: tells the reader that the difference between the groups wasn’t important
no significant intergroup difference: there was no important difference between the study and control group
the conventional group: the group with the normal procedure that is being compare against
Further study for this week
Try writing up some results of a recent experiment you have made including tables of data and descriptions about what can be understood from the data. Try the short quiz below to test your understanding.