**Select menu: Stats | Survival Analysis | Parametric Models**

Models survival times assuming that they follow either an exponential, Weibull, extreme-value, log-logistic or lognormal distribution. It caters for right-censored observations, where the subject concerned survived the trial. The log-logistic distribution can be used to cater for left-censored observations.

- After you have imported your data, from the menu select

**Stats | Survival Analysis | Parametric Models**. - Fill in the fields as required then click
**Run**.

You can set additional Options then after running, you can save the results by clicking Save.

## Available data

This lists data structures appropriate to the current input field. The contents will change as you move from one field to the next. You can double-click a name to copy it to the current input field or type it in.

## Time points

Time of each observation.

## Censored

Variate containing the values 0 and 1 to indicate whether the corresponding time point is censored (1) or not (0). For the log-logistic distribution left censored observations can be specified by using -1.

## Distribution

Distribution of the survival times. Can be either Exponential, Weibull, Extreme value, Log-logistic and Lognormal.

## Model

The model terms to be fitted are specified by entering a model formula.