Reproducible analysis of disease space via principal components using the novel R package syndRomics

  1. Abel Torres-Espín
  2. Austin Chou
  3. J Russell Huie
  4. Nikos Kyritsis
  5. Pavan S Upadhyayula
  6. Adam R Ferguson  Is a corresponding author
  1. Weill Institute for Neurosciences, Brain and Spinal Injury Center (BASIC), University of California, San Francisco (UCSF), United States
  2. Department of Neurological Surgery, University of California San Francisco (UCSF), United States
  3. Zuckerberg San Francisco General Hospital and Trauma Center, United States
  4. School of Medicine, University of California San Diego (UCSD), United States
  5. San Francisco VA Health Care System, United States
7 figures, 12 tables and 3 additional files

Figures

Summary of the syndromic framework and analysis steps.

(A) The theoretical framework of syndromic analysis. The intersection between different outcome measures can create a multivariate measure (principal component if PCA is used) to explain different patterns of variance in the data. The conceptual union of three van diagram forms the core of the syndromic plot symbolizing the multidimensional measure. (B) The different steps of the workflow to using PCA such as for disease pattern analysis.

Implementation of permutation algorithms.

(A) Shows a schematic example of the permutation procedure permD where all the variables are permuted concomitantly but independently. (B) Shows a schematic example of the permutation procedure permV where variables are permuted one at the time for each permutation samples (P), keeping the other variables as in the original dataset. (C) The implemented algorithm for the permutation test algorithm using permD: each one to n permutation sample (P) consist on a random reorganization of observations inside each variable independently and concomitantly for each variable. For each P sample, a PCA is run and either the loadings, communalities or VAF are calculated. All P PCA solutions form the null distribution for non-parametric hypothesis testing of loadings or VAF. (D) The permutation test algorithm for loadings under permV is performed with and extra step of Procrustes rotation between each of the P samples to the parent component loadings. The P rotated loadings will then form the null distribution for each variable.

Figure 3 with 1 supplement
Permutation test of case study.

(A) The graph shows the original VAF for the first five PCs and the average and 95% confidence interval VAF of the permuted PCA distribution (p=10000) using the permD method. * Statistical difference for the non-parametric test at alpha = 0.05 and adjusted p value by BH. The three first PCs were selected for the subsequent analysis. (B) Barmap of the original communalities (bars) and the permuted distribution (permV, p=3000) for each variable calculated over the first three PCs. (C) Barmap of the original loadings (bars) and the permuted distribution (permV, p=3000) for each variable and each of the first three PCs. Solid dotes represent the mean of the permuted distribution and error bars represent the 95% CI.

Figure 3—source data 1

csv file containing the source data for panel A in Figure 3.

https://cdn.elifesciences.org/articles/61812/elife-61812-fig3-data1-v2.csv
Figure 3—source data 2

csv file containing the source data for panel B in Figure 3.

https://cdn.elifesciences.org/articles/61812/elife-61812-fig3-data2-v2.csv
Figure 3—source data 3

csv file containing the source data for panel C in Figure 3.

https://cdn.elifesciences.org/articles/61812/elife-61812-fig3-data3-v2.csv
Figure 3—figure supplement 1
Missing data analysis of the first case study.

(A) Shadow plot of missing data for the variables selected for the case study. Approximately 17% are missing values. Four patterns of missingness are observed as shown by the upset plot (B), three patterns with involving more than one variable and a pattern with a single variable. The fact that most missing values are across variables for the same subject (two biggest missing pattern sets) suggest data is missing at random (MAR), meaning there is an external reason to the observed values for that missing. In order to assess the stability of the PCA analysis by performing multiple imputation, we calculated the distribution of loadings generated by 50 multiple imputed datasets (C). The small variation around a pooled loading (average, bar) suggest a very small variation introduced by imputing the data, further corroborated by the component similarity measures for the first three PCs (Tables 46). Solid dots represent the mean of the multiple imputed loading distribution and error bars represent the 95% CI.

Figure 4 with 1 supplement
Implementation of bootstrapping algorithm.

(A) shows a schematic of the bootstrapping procedure where a bootstrap sample is generated by resampling the original samples as many times as there are samples in the original dataset but allowing for replacement. The bootstrapping algorithm for loadings is (B): for each of 1 to n bootstrap sample (b), run a PCA with the same specifications than the parent PCA on the original sample. The bootstrapping method (e.g. balanced bootstrap) can be specified with the sim argument passed to the boot() function of the boot R package. Then, the sample component loading is obtained from the PCA of the bootstrapped sample and a Procrustes rotation of the loading matrix is applied over the parent loading matrix to correct for PCA indeterminacies (C; see text). All b rotated loadings form the bootstrapped distribution of loadings. The component similarity of each b loading with the parent loading solution can be calculated to generate the bootstrapped distribution of component similarity. From these distributions, the average and confidence interval are estimated.

Figure 4—figure supplement 1
Computation time for resampling.

The pc_stability() and permut_pca_test() functions were run 10 times for different number of bootstrapped (A–C) and permuted (D–F) samples (10, 25, 50, 100, 250, 500, 750, 1000, 1500, or 2000) for two datasets with different sizes (n:rows x p:columns; 159 × 18 or 1590 × 54). The computation time (in seconds) increased linearly with the increase of samples, being the rate of increasement higher for the bigger dataset (A and D). The small margin of error for each condition (standard deviation) reflects the little effect of different runs (with different random generated numbers) on the computation time. The computed loading for a variable with high loading (~|0.75|) and another for low loading (~|0.25|) of the PC1 for each condition is shown in (B and E). As the sample size increases, the variability around the loading average decreases. The width of the 95% CI (based on t-distribution with 9 degrees of freedom) for each condition is shown (C and F) as measure of precision around the loading average estimate. The precision is smaller with the smaller size of the data, indicating that the uncertainty of the estimated averaged loading is affected by the data volume. The standard 1000 samples are a good compromise between computation time and precision of the estimated loadings for the big dataset, but smaller dataset might require bigger resamples.

Principal component (PC) stability results of case study.

Barmap plot of the bootstrap distribution of loadings (A) and communalities (B) representing the average and the 95% confidence interval of 3000 bootstrapped samples for the first three PCs. Assessing the confidence region offers an indicator of the uncertainty of the estimated loadings for each variable on each PC. Solid dots represent the mean of the bootstrap distribution and error bars represent the 95% CI.

Visualization of PCA solutions for syndromic analysis.

(A–C) show the layout of the PC1, PC2, and PC3 syndromic plot of variables |loadings| > 0.45, respectively: arrows pointing the center of the plot representing the magnitude (arrow thickness and color saturation) and direction (color) of the loadings of selected variables. (D) illustrate an example of the same loading solution plotted by a heatmap. * Indicates variables with |loadings| > 0.21, 0.25 or 0.4 for PC1, PC2, and PC3, respectively.

Figure 7 with 1 supplement
Analysis of case study 2 using non-linear PCA and the syndRomics package.

(A-B) show thebarmap plots for the loadings for the first three PCs with the 95% CI generated from 500 permutationand 1000 bootstrap resamples. (C-D) show the syndromic plots for the PC1 (VAF=25.8%) and PC2(VAF=10.6%) for |loading|>0.4. Error bars represent the 95%CI of the resampling method.

Figure 7—figure supplement 1
Missing data analysis of the second case study.

(A) Shadow plot of missing data for the variables selected for the case study. Approximately 22% are missing values. The fact that most missing values are across variables for the same subject (two biggest missing pattern sets) suggest data is missing at random (MAR), meaning there is an external reason to the observed values for that missing. In order to assess the stability of the PCA analysis by performing multiple imputation, we calculated the distribution of loadings generated by 50 multiple imputed datasets (B). Solid dots represent the mean of the multiple imputed loading distribution and error bars represent the 95% CI.

Tables

Table 1
List of variables included in the first case study.
VariableDefinition
wtChngChange of animal weight (grams) from day of Injury to 6 weeks post-injury
RFSLCATWALK SYSTEM RightForelimb StrideLength at 6 weeks post-injury
LFSLCATWALK SYSTEM LeftForelimb StrideLength at 6 weeks post-injury
RHSLCATWALK SYSTEM RightHindlimb StrideLength at 6 weeks post-injury
LHSLCATWALK SYSTEM LeftHindlimb StrideLength at 6 weeks post-injury
RFPACATWALK SYSTEM RightForelimb PrintArea at 6 weeks post-injury
LFPACATWALK SYSTEM LeftForelimb PrintArea at 6 weeks post-injury
RHPACATWALK SYSTEM RightHindlimb PrintArea at 6 weeks post-injury
LHPACATWALK SYSTEM LeftHindlimb PrintArea at 6 weeks post-injury
StepDistRFCATWALK SYSTEM RightForelimb Step Distribution Deviation from 25% at 6 weeks post-injury
StepDistLFCATWALK SYSTEM LeftForelimb Step Distribution Deviation from 25% at 6 weeks post-injury
StepDistRHCATWALK SYSTEM RightHindlimb Step Distribution Deviation from 25% at 6 weeks post-injury
StepDistLHCATWALK SYSTEM LeftHindlimb Step Distribution Deviation from 25% at 6 weeks post-injury
TotalSubscoreTotal BBB Subscore at 6 weeks post-injury
BBB FergTransBBB Ferguson Transformation score 6 weeks post-injury
GroomGrooming Score 6 weeks post-injury
PawPLPawPlacement score 6 weeks post-injury
ForelimbOpenFieldForelimb openfield score at 6 weeks post-injury
Table 2
List of variables included in the second case study.
VariableDescriptionValues
CT_MarshallMarshall CT ScoreRange from 1 to 6
CT_RotterdamRotterdam CT ScoreRange from 1 to 6
CT_brain_pathologyCT Brain Pathology0 = ‘No’, 1 = ‘Yes’
CT_skull_FXCT Skull Fracture0 = ‘No’, 1 = ‘Yes’
CT_skullbase_FXCT Skull Base Fracture0 = ‘No’, 1 = ‘Yes’
CT_facial_FXCT Facial Fracture0 = ‘No’, 1 = ‘Yes’
CT_EDHCT Epidural Hematoma0 = ‘No’, 1 = ‘Yes’
CT_SDHCT Subdural Hematoma0 = ‘No’, 1 = ‘Yes’
CT_SAHCT Subarachnoid Hemorrhage0 = ‘No’, 1 = ‘Yes’
CT_contusionCT Contusion0 = ‘No’, 1 = ‘Yes’
CT_midlineshiftCT Midline Shift0 = ‘No’, 1 = ‘Yes’
CT_cisterncompCT Cisternal Compression0 = ‘No’, 1 = ‘Yes’
PTSD_diagnosis_6moPTSD DSM-IV Diagnosis (6 months)0 = ‘No’, 1 = ‘Yes’
GOSE_3moGOSE Score (3 months)Range from 1 to 8
GOSE_6moGOSE Score (6 months)Range from 1 to 8
WAIS_PSI_6moWAIS PSI Composite Score (6 months)Range from 50 to 150
CVLT_short_6moCVLT Short Delay Cued Recall Standard Score (6 months)Range from −4.0–2.5
CVLT_long_6moCVLT Long Delay Cued Recall Standard Score (6 months)Range from −3.5–2.5
SNP_COMTCOMT SNP Genotype1 = ‘Met/Met’, 2 = ‘Met/Val’, 3 = ‘Val/Val’
SNP_DRD2DRD2 SNP Genotype1 = ‘C/C’, 2 = ‘C/T’, 3 = ‘T/T’
SNP_PARP1PARP1 SNP Genotype1 = ‘A/A’, 2 = ‘A/T’, 3 = ‘T/T’
SNP_ANKK1_Gly318ArgANKK1 SNP Gly318Arg1 = ‘A/A’, 2 = ‘A/G’, 3 = ‘G/G’
SNP_ANKK1_Gly442ArgANKK1 SNP Gly442Arg1 = ‘C/C’, 2 = ‘C/G’, 3 = ‘G/G’
SNP_ANKK1_Glu713LysANKK1 SNP Glu713Lys1 = ‘C/C’, 2 = ‘C/T’, 3 = ‘T/T’
Table 3
Communalities of first three PCs on permutation test with 3000 random permutations using permV and adjusting p values with BH.
VariableOriginal communalitiesPermuted averageLower 95% CIUpper 95% CIp valueAdjusted p value
wtChng0.460.060.010.200.00030.0004
RFSL0.590.060.000.200.00030.0004
RFPA0.850.060.000.170.00030.0004
StepDistRF0.540.050.000.170.00030.0004
LFSL0.570.060.000.180.00030.0004
LFPA0.610.060.000.200.00030.0004
StepDistLF0.710.050.000.170.00030.0004
RHSL0.880.060.000.180.00030.0004
RHPA0.810.060.000.190.00030.0004
StepDistRH0.270.060.000.180.00200.0020
LHSL0.790.060.000.200.00030.0004
LHPA0.790.070.000.230.00030.0004
StepDistLH0.460.060.000.200.00030.0004
Groom0.530.060.000.170.00030.0004
PawPL0.700.060.000.170.00030.0004
BBB_FergTrans0.660.050.000.170.00030.0004
TotalSubscore0.400.050.000.170.00030.0004
ForelimbOpenField0.370.050.000.180.00030.0004
Table 4
PC1 loading results of permutation test for the first case study with 3000 random permutations using permV and adjusting p values with BH.
VariableOriginal loadingPermuted averageLower 95% CIUpper 95% CIp valueAdjusted p value
wtChng−0.340.00−0.190.180.00030.0007
TotalSubscore−0.560.00−0.210.190.00030.0007
StepDistRH0.890.01−0.200.210.00030.0007
StepDistRF−0.650.00−0.190.170.00030.0007
StepDistLH−0.280.00−0.180.180.00430.0084
StepDistLF0.540.01−0.180.180.00030.0007
RHSL−0.760.00−0.190.190.00030.0007
RHPA−0.850.00−0.170.190.00030.0007
RFSL0.740.01−0.180.190.00030.0007
RFPA−0.250.00−0.180.180.00630.0114
PawPL−0.760.00−0.170.170.00030.0007
LHSL0.620.00−0.180.180.00030.0007
LHPA−0.240.00−0.190.170.01630.0259
LFSL0.380.01−0.170.200.00030.0007
LFPA−0.54−0.01−0.210.200.00030.0007
Groom0.490.00−0.200.190.00030.0007
ForelimbOpenField0.20−0.01−0.190.180.03230.0459
BBB_FergTrans0.510.01−0.180.190.00030.0007
Table 5
PC2 loading results of permutation test for the first case study with 3000 random permutations using permV and adjusting p values with BH.
VariableOriginal loadingPermuted averageLower 95% CIUpper 95% CIp valueAdjusted p value
wtChng−0.370.00−0.230.220.00230.0047
TotalSubscore−0.48−0.01−0.230.210.00030.0007
StepDistRH−0.07−0.01−0.230.230.51220.5644
StepDistRF0.280.00−0.230.210.01430.0234
StepDistLH−0.660.01−0.230.240.00030.0007
StepDistLF0.270.00−0.220.230.02030.0305
RHSL0.340.00−0.240.230.00030.0007
RHPA−0.300.00−0.210.210.00830.0145
RFSL0.400.00−0.220.250.00030.0007
RFPA0.210.00−0.220.220.06430.0868
PawPL−0.300.00−0.190.220.00230.0047
LHSL0.420.01−0.210.230.00030.0007
LHPA0.120.00−0.240.220.31820.3656
LFSL−0.620.00−0.250.250.00030.0007
LFPA0.630.00−0.240.260.00030.0007
Groom−0.650.00−0.220.230.00030.0007
ForelimbOpenField−0.59−0.01−0.250.230.00030.0007
BBB_FergTrans−0.32−0.01−0.220.220.00230.0047
Table 6
PC3 loading results of permutation test for the first case study with 3000 random permutations using permV and adjusting p values with BH.
VariableOriginal loadingPermuted averageLower 95% CIUpper 95% CIp valueAdjusted p value
wtChng0.460.00−0.430.410.01830.0283
TotalSubscore0.220.00−0.320.340.24630.2955
StepDistRH0.230.01−0.320.350.23030.2826
StepDistRF−0.190.01−0.320.340.31020.3642
StepDistLH0.230.00−0.340.360.20830.2615
StepDistLF0.50−0.01−0.360.400.00630.0114
RHSL0.120.00−0.350.330.53820.5698
RHPA0.260.00−0.350.350.19030.2446
RFSL0.320.00−0.360.410.10430.1374
RFPA0.410.00−0.340.350.02230.0326
PawPL0.35−0.01−0.370.350.05830.0807
LHSL0.480.01−0.390.440.01230.0208
LHPA0.620.00−0.380.350.00030.0007
LFSL−0.050.00−0.350.330.80010.8308
LFPA−0.12−0.01−0.320.340.53020.5698
Groom0.030.01−0.340.340.86800.8844
ForelimbOpenField−0.140.01−0.320.340.48020.5402
BBB_FergTrans0.000.02−0.330.330.99000.9900
Table 7
Similarity metrics of the first three PCs between 50 multiple imputed datasets for the first case study.

Silent cutoff for S index was set at |0.2|.

CC indexr indexRMSES index
PCMeanSDMeanSDMeanSDMeanSD
PC10.9990.00030.9990.00030.0210.0040.9910.015
PC20.9980.00050.9980.00050.0210.0040.930.042
PC30.9970.0010.9960.0020.0220.0050.9650.03
Table 8
PC1 loading results of permutation test for the second case study with 500 random permutations using permV and adjusting p values with BH.
VariableOriginal loadingPermuted averageLower 95% CIUpper 95% CIp valueAdjusted p value
CT_brain_pathology0.4405890.010978−0.176060.2020950.0019960.003194
CT_cisterncomp0.18440.003484−0.169470.2098010.0538920.061591
CT_contusion0.3826120.008019−0.170530.1873630.0019960.003194
CT_EDH0.2563680.015695−0.162390.1901670.0019960.003194
CT_facial_FX0.2673220.029918−0.164650.2020630.0119760.015128
CT_Marshall0.2352420.003685−0.169120.1912290.009980.013307
CT_midlineshift0.002539−0.01082−0.20050.1909560.9880240.988024
CT_Rotterdam0.2746990.010723−0.171760.1956460.0019960.003194
CT_SAH0.3765960.009848−0.161850.1916710.0019960.003194
CT_SDH0.3775420.018196−0.154880.1965380.0019960.003194
CT_skull_FX0.4044470.020049−0.153980.1980670.0019960.003194
CT_skullbase_FX0.3181790.019653−0.186910.1955470.0019960.003194
CVLT_long_6mo−0.70622−0.05218−0.375820.2957690.0019960.003194
CVLT_short_6mo−0.63345−0.04306−0.3780.2586020.0019960.003194
GOSE_3mo−0.32848−0.00894−0.174650.1774560.0019960.003194
GOSE_6mo−0.25329−0.00613−0.192980.1763430.0039920.005988
PTSD_diagnosis_6mo0.1887430.013079−0.158850.1903640.0419160.050299
SNP_ANKK1_Glu713Lys0.3580710.028077−0.146470.1909650.0019960.003194
SNP_ANKK1_Gly318Arg0.6136240.043104−0.177470.2440820.0019960.003194
SNP_ANKK1_Gly442Arg−0.25194−0.02327−0.197560.165770.0059880.008454
SNP_COMT0.0366870.001474−0.175110.1725430.6966070.726894
SNP_DRD2−0.62858−0.05017−0.241050.1683590.0019960.003194
SNP_PARP1−0.05912−0.00576−0.181010.1664750.5129740.559608
WAIS_PSI_6mo−0.36179−0.0144−0.196460.1680750.0019960.003194
Table 9
PC2 loading results of permutation test for the second case study with 500 random permutations using permV and adjusting p values with BH.
VariableOriginal loadingPermuted averageLower 95% CIUpper 95% CIp valueAdjusted p value
CT_brain_pathology0.6623780.021655−0.120840.1588390.0019960.002818
CT_cisterncomp0.7099890.024823−0.141810.1781260.0019960.002818
CT_contusion0.5963110.01766−0.122220.1577850.0019960.002818
CT_EDH0.2530790.002735−0.136620.1353480.0019960.002818
CT_facial_FX0.1426020.000971−0.124660.1335740.0419160.055888
CT_Marshall0.8098470.026415−0.134380.1737710.0019960.002818
CT_midlineshift0.696050.034813−0.129170.1899170.0019960.002818
CT_Rotterdam0.7534980.01539−0.132050.1786380.0019960.002818
CT_SAH0.6890840.017617−0.124250.1552460.0019960.002818
CT_SDH0.6987280.017798−0.120570.1619010.0019960.002818
CT_skull_FX0.4931990.007764−0.139210.1618880.0019960.002818
CT_skullbase_FX0.2946910.003769−0.128630.1413750.0019960.002818
CVLT_long_6mo0.0560950.019229−0.215440.234990.6746510.703983
CVLT_short_6mo0.1156630.020014−0.201520.2151210.3532930.423952
GOSE_3mo−0.43692−0.00787−0.143010.1395080.0019960.002818
GOSE_6mo−0.40155−0.00849−0.144840.1183860.0019960.002818
PTSD_diagnosis_6mo0.004807−0.00863−0.148630.1404180.940120.94012
SNP_ANKK1_Glu713Lys−0.26204−0.01604−0.157570.1321640.0019960.002818
SNP_ANKK1_Gly318Arg−0.28622−0.01954−0.159860.1336370.0019960.002818
SNP_ANKK1_Gly442Arg0.033308−0.00308−0.126620.1293710.6307390.688078
SNP_COMT−0.0406−0.00094−0.140470.1407830.5888220.67294
SNP_DRD20.3074570.023806−0.115490.1787770.0019960.002818
SNP_PARP10.2442460.000876−0.148010.1331310.0019960.002818
WAIS_PSI_6mo−0.132520.001279−0.131670.1349850.0558880.070596
Table 10
PC3 loading results of permutation test for the second case study with 500 random permutations using permV and adjusting p values with BH.
VariableOriginal loadingPermuted averageLower 95% CIUpper 95% CIp valueAdjusted p value
CT_brain_pathology0.1101490.002819−0.302420.3093760.5289420.641916
CT_cisterncomp−0.32449−0.00334−0.333790.3056720.0479040.13839
CT_contusion0.060972−0.00689−0.314440.2701760.6986030.728977
CT_EDH0.104859−0.00125−0.273520.3215350.5189620.641916
CT_facial_FX0.3716490.062687−0.316920.3556910.019960.07984
CT_Marshall−0.24284−0.01023−0.30380.2881710.1297410.259481
CT_midlineshift−0.30562−0.01988−0.328880.3087850.0638720.153293
CT_Rotterdam−0.24002−0.01377−0.328840.2929590.1616770.284003
CT_SAH0.16969−0.0017−0.304690.3238960.3473050.520958
CT_SDH0.1641460.011718−0.335370.3080910.3393210.520958
CT_skull_FX0.309110.013422−0.283090.3174830.0479040.13839
CT_skullbase_FX0.4125070.027909−0.297480.3500750.0059880.047904
CVLT_long_6mo0.0715610.007602−0.267950.3300450.6626750.722918
CVLT_short_6mo0.014780.003403−0.294150.3413270.9221560.922156
GOSE_3mo0.5121730.027225−0.30350.3474520.0019960.023952
GOSE_6mo0.5196540.030422−0.281790.3610450.0019960.023952
PTSD_diagnosis_6mo−0.29067−0.02728−0.310230.2279070.0518960.13839
SNP_ANKK1_Glu713Lys−0.47272−0.02347−0.400380.3688740.0079840.047904
SNP_ANKK1_Gly318Arg−0.14092−0.02104−0.341640.277990.3792420.5354
SNP_ANKK1_Gly442Arg−0.34766−0.02656−0.383320.3539870.0838320.182907
SNP_COMT−0.101710.001249−0.266350.2846470.534930.641916
SNP_DRD20.0812960.013862−0.29120.3231140.614770.702595
SNP_PARP10.2330070.010172−0.290540.3183850.1656690.284003
WAIS_PSI_6mo0.397060.017391−0.270220.3377130.0119760.057485
Table 11
Similarity metrics of the first 3PCs between 50 multiple imputed datasets for the second case study.

Silent cutoff for S index was set at |0.2|.

CC indexr indexRMSES index
PCMeanSDMeanSDMeanSDMeanSD
PC10.9550.0350.9580.0330.0940.060.880.037
PC20.9920.0040.9910.00540.0560.0390.930.04
PC30.870.0970.8740.0970.1330.1270.710.06
Table 12
Template/example of data.frame containing loadings that can be passed to the visualization functions (only the loadings for the first three PCs are shown).
VariablePC1PC2PC3
 wtChng−0.34−0.370.46
 TotalSubscore−0.56−0.480.22
 StepDistRH0.89−0.070.23
 StepDistRF−0.650.28−0.19
 StepDistLH−0.28−0.660.23
 StepDistLF0.540.270.50
 RHSL−0.760.340.12
 RHPA−0.85−0.300.26
 RFSL0.740.400.32
 RFPA−0.250.210.41
 PawPL−0.76−0.300.35
 LHSL0.620.420.48
 LHPA−0.240.120.62
 LFSL0.38−0.62−0.05
 LFPA−0.540.63−0.12
 Groom0.49−0.650.03
 ForelimbOpenField0.20−0.59−0.14
 BBB_FergTrans0.51−0.32−0.03

Additional files

Source code 1

The R script reproducing the analysis of this manuscript in a Rmarkdown file.

https://cdn.elifesciences.org/articles/61812/elife-61812-code1-v2.zip
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https://cdn.elifesciences.org/articles/61812/elife-61812-code2-v2.zip
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https://cdn.elifesciences.org/articles/61812/elife-61812-transrepform-v2.docx

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  1. Abel Torres-Espín
  2. Austin Chou
  3. J Russell Huie
  4. Nikos Kyritsis
  5. Pavan S Upadhyayula
  6. Adam R Ferguson
(2021)
Reproducible analysis of disease space via principal components using the novel R package syndRomics
eLife 10:e61812.
https://doi.org/10.7554/eLife.61812