Problem with meta forestplot nullrefline command

[Kai Schulze]

Hi!

I hope everyone is well!

I meta-analyse Hazard ratios from epidemiological studies using the meta forestplot command. I want to draw a vertical line at 1. If I use the nullrefline option, it draws a line at 0. In the documentation, there's an example in which a line at 1 is drawn (example 10). Unfortunately, I can't replicate that, as in I can't see why the line is at 1 in this case. Is there any way to specify that a vertical line is drawn at 1?

Any leads would be much appreciated.

All the very best,
Kai

[David Fisher]

Hi Kai,

Assuming that meta forestplot works the same way as (user-written, from SSC) metan or admetan, the reason is probably due to whether the effect sizes are exponentiated or not. Odds ratios, risk ratios and hazard ratios are exponentiated, and the null effect is at 1. Otherwise, the null effect is at zero. So, if you have hazard ratios, you should take logarithms prior to calling meta summarize, and then use the eform option, as described in Example 8 under "help meta summarize".

Best wishes,

David.

[Kai Schulze]

Thanks David! That worked!