1. Null hypothesis: (Food) antigen X does not inhibit α-gliadin antibody binding relative to control.



2. Alternate hypothesis: (Food) antigen X inhibits α-gliadin antibody binding relative to control

Biologists typically use a threshold value of p ≤ 0.05, which is considered to be statistically significant, and p ≥ 0.05 as non significant (this threshold value may change depending on the application and appropriateness for a given assay). A p ≤ 0.05 means that if we assume the null hypothesis (no effect) to be true, the chance of getting a result at least as large as what was observed, is equal to (or less than) 5%. Therefore, if we get a very small p-value (under 5%), we can reject the null hypothesis because the frequency of seeing such results under this hypothesis is so small that it’s incompatible. Meaning these results are unlikely to occur under the null hypothesis/model. The smaller the p-value, the less consistent the results are with the null hypothesis. Therefore, we might accept the alternative hypothesis, which is likely to be more compatible with the observed results.

Observing the “p-values” reported in Table 2:

Using the p ≤ 0.05 threshold, we can reject the null hypothesis for α-gliadin (outlined in blue, positive control). If we’re generous and we increase our threshold to p ≤ 0.1 (meaning the frequency of getting results at least this large under the null hypothesis is less than or equal to 10%), we can include yeast, millet, and corn.

p = 0.5 means that there is a 50% chance of getting results at least as large as what was observed under the null hypothesis of no effect. In other words, if we repeated this experiment several times, half of the time, we’d see differences at least this big, even if there was no actual effect.