

# Two sample MR report

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## Sphingomyelin (d34:2) levels against finn-b-I9_PVT_EXNONE

Date: **16 December, 2025**

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### Results from two sample MR:


|method                    | nsnp|          b|        se|      pval|
|:-------------------------|----:|----------:|---------:|---------:|
|MR Egger                  |    8| -0.7133208| 1.0534375| 0.5235544|
|Weighted median           |    8|  0.7047838| 0.4927412| 0.1526216|
|Inverse variance weighted |    8|  0.8183605| 0.3736871| 0.0285270|
|Simple mode               |    8|  0.0491949| 0.8187553| 0.9537673|
|Weighted mode             |    8|  1.1022141| 0.7086119| 0.1637894|

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### Heterogeneity tests


|method                    |        Q| Q_df|    Q_pval|
|:-------------------------|--------:|----:|---------:|
|MR Egger                  | 4.558339|    6| 0.6015701|
|Inverse variance weighted | 6.976724|    7| 0.4313073|

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### Test for directional horizontal pleiotropy


| egger_intercept|        se|      pval|
|---------------:|---------:|---------:|
|       0.2624364| 0.1687568| 0.1709173|

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### Test that the exposure is upstream of the outcome


| snp_r2.exposure| snp_r2.outcome|correct_causal_direction | steiger_pval|
|---------------:|--------------:|:------------------------|------------:|
|       0.0003382|              0|TRUE                     |    0.1338915|

Note - R^2 values are approximate

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### Forest plot of single SNP MR

![plot of chunk chunk5](figure/Sphingomyelin_d342_levels_against_finnbI9PVTEXNONEchunk5-1.png)

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### Comparison of results using different MR methods

![plot of chunk chunk6](figure/Sphingomyelin_d342_levels_against_finnbI9PVTEXNONEchunk6-1.png)

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### Funnel plot

![plot of chunk chunk7](figure/Sphingomyelin_d342_levels_against_finnbI9PVTEXNONEchunk7-1.png)

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### Leave-one-out sensitivity analysis

![plot of chunk chunk8](figure/Sphingomyelin_d342_levels_against_finnbI9PVTEXNONEchunk8-1.png)
