Independent Samples Z-Test - Comparing Two Proportions (Un-Pooled)

Where $g_{1}$ and $g_{2}$ are the two proportions and $n_{1}$ and $n_{2}$ are the sample sizes:

$z = \frac{g_{1} - g_{2}}{\sqrt{\frac{g_{1} (1 - g_{1})}{n_{1}} + \frac{g_{2} (1 - g_{2})}{n_{2}}}}$

where $p = 2 (1 - Φ (| z |))$ .