def fit_cox(
train_df: Union[pd.DataFrame, str],
covariates: List[str],
test_df: Union[pd.DataFrame, str] = None,
strata: List[str] = None,
plot: bool = False,
process_dir: str = None,
):
if isinstance(train_df, str):
train_df = pd.read_csv(train_df)
if isinstance(test_df, str):
test_df = pd.read_csv(test_df)
cphf = CoxPHFitter()
included_cols = ["duration", "event"] + list(covariates)
print(train_df.columns)
cphf.fit(
train_df[included_cols],
duration_col="duration",
event_col="event",
strata=strata,
)
results = {
"log_likelihood":
cphf.log_likelihood_,
"concordance_index":
cphf.concordance_index_,
"log_likelihood_ratio_test_pvalue":
cphf.log_likelihood_ratio_test().p_value,
}
if test_df is not None:
results["test_log_likelihood"] = cphf.score(
test_df[included_cols], scoring_method="log_likelihood")
results["test_concordance_index"] = cphf.score(
test_df[included_cols], scoring_method="concordance_index")
if plot and process_dir is not None:
plt.figure(figsize=(5, 10))
cphf.plot()
plt.savefig(os.path.join(process_dir, "hazard_plot.pdf"))
if process_dir is not None:
cphf.summary.to_csv(os.path.join(process_dir, "summary.csv"))
save_dict_to_json(os.path.join(process_dir, "results.json"), results)
return results, cphf
def cox_fit(df, prior, later, nexposed, nindivs, lagged_hr_cut_year,
is_sex_specific, res_writer, error_writer):
"""Fit the data for the Cox regression and write output to result file"""
logger.info(f"Fitting data to Cox model (lag: {lagged_hr_cut_year})")
# First try with a somewhat big step_size to go fast, retry later
# with a lower step_size to help with convergence.
step_size = 1.0
cph = CoxPHFitter()
cox_fit_success = False # keep track of when we need to write out the results
# Set covariates depending on outcome being sex-specific
cols = ["duration", "outcome", "pred_prior", "birth_year", "SMOKER", "BMI"]
if not is_sex_specific:
cols.append("SEX")
df = df.loc[:, cols]
# Compute the median duration for those with the prior->outcome association
median_duration = df.loc[df.pred_prior & df.outcome, "duration"].median()
# Set default values in case of error
pred_coef = np.nan
pred_se = np.nan
pred_hr = np.nan
pred_ci_lower = np.nan
pred_ci_upper = np.nan
pred_pval = np.nan
pred_zval = np.nan
year_coef = np.nan
year_se = np.nan
year_hr = np.nan
year_ci_lower = np.nan
year_ci_upper = np.nan
year_pval = np.nan
year_zval = np.nan
smoker_coef = np.nan
smoker_se = np.nan
smoker_hr = np.nan
smoker_ci_lower = np.nan
smoker_ci_upper = np.nan
smoker_pval = np.nan
smoker_zval = np.nan
bmi_coef = np.nan
bmi_se = np.nan
bmi_hr = np.nan
bmi_ci_lower = np.nan
bmi_ci_upper = np.nan
bmi_pval = np.nan
bmi_zval = np.nan
sex_coef = np.nan
sex_se = np.nan
sex_hr = np.nan
sex_ci_lower = np.nan
sex_ci_upper = np.nan
sex_pval = np.nan
sex_zval = np.nan
nsubjects = np.nan
nevents = np.nan
partial_log_likelihood = np.nan
concordance = np.nan
log_likelihood_ratio_test = np.nan
log_likelihood_ndf = np.nan
log_likelihood_pval = np.nan
try:
cph.fit(
df,
duration_col="duration",
event_col="outcome",
show_progress=False,
step_size=step_size,
)
except (ConvergenceError, Warning):
logger.debug(
f"Failed to fit Cox model for pair ({prior}, {later}) with step_size={step_size}, retrying with lower step_size"
)
# Retry with lower step_size to help with convergence
step_size = 0.1
try:
cph.fit(
df,
duration_col="duration",
event_col="outcome",
show_progress=False,
step_size=step_size,
)
except (ConvergenceError, Warning) as e:
logger.warning(
f"Failed to fit Cox model for pair ({prior}, {later}) after lowering step_size to {step_size} to fit Cox model"
)
error_writer.writerow(
[prior, later, lagged_hr_cut_year,
type(e), e])
else:
logger.debug(
f"Success when retrying with lower step_size={step_size}")
cox_fit_success = True
else:
cox_fit_success = True
if cox_fit_success:
# Save results
pred_coef = cph.params_["pred_prior"]
pred_se = cph.standard_errors_["pred_prior"]
pred_hr = np.exp(pred_coef)
pred_ci_lower = np.exp(pred_coef - 1.96 * pred_se)
pred_ci_upper = np.exp(pred_coef + 1.96 * pred_se)
pred_pval = cph.summary.p["pred_prior"]
pred_zval = cph.summary.z["pred_prior"]
year_coef = cph.params_["birth_year"]
year_se = cph.standard_errors_["birth_year"]
year_hr = np.exp(year_coef)
year_ci_lower = np.exp(year_coef - 1.96 * year_se)
year_ci_upper = np.exp(year_coef + 1.96 * year_se)
year_pval = cph.summary.p["birth_year"]
year_zval = cph.summary.z["birth_year"]
smoker_coef = cph.params_["SMOKER"]
smoker_se = cph.standard_errors_["SMOKER"]
smoker_hr = np.exp(smoker_coef)
smoker_ci_lower = np.exp(smoker_coef - 1.96 * smoker_se)
smoker_ci_upper = np.exp(smoker_coef + 1.96 * smoker_se)
smoker_pval = cph.summary.p["SMOKER"]
smoker_zval = cph.summary.z["SMOKER"]
bmi_coef = cph.params_["BMI"]
bmi_se = cph.standard_errors_["BMI"]
bmi_hr = np.exp(bmi_coef)
bmi_ci_lower = np.exp(bmi_coef - 1.96 * bmi_se)
bmi_ci_upper = np.exp(bmi_coef + 1.96 * bmi_se)
bmi_pval = cph.summary.p["BMI"]
bmi_zval = cph.summary.z["BMI"]
if not is_sex_specific:
sex_coef = cph.params_["SEX"]
sex_se = cph.standard_errors_["SEX"]
sex_hr = np.exp(sex_coef)
sex_ci_lower = np.exp(sex_coef - 1.96 * sex_se)
sex_ci_upper = np.exp(sex_coef + 1.96 * sex_se)
sex_pval = cph.summary.p["SEX"]
sex_zval = cph.summary.z["SEX"]
nsubjects = cph._n_examples
nevents = cph.event_observed.sum()
partial_log_likelihood = cph._log_likelihood
concordance = cph.score_
with np.errstate(invalid="ignore", divide="ignore"):
sr = cph.log_likelihood_ratio_test()
log_likelihood_ratio_test = sr.test_statistic
log_likelihood_ndf = sr.degrees_freedom
log_likelihood_pval = sr.p_value
res_writer.writerow([
prior,
later,
nexposed,
nindivs,
lagged_hr_cut_year,
median_duration,
pred_coef,
pred_se,
pred_hr,
pred_ci_lower,
pred_ci_upper,
pred_pval,
pred_zval,
year_coef,
year_se,
year_hr,
year_ci_lower,
year_ci_upper,
year_pval,
year_zval,
sex_coef,
sex_se,
sex_hr,
sex_ci_lower,
sex_ci_upper,
sex_pval,
sex_zval,
smoker_coef,
smoker_se,
smoker_hr,
smoker_ci_lower,
smoker_ci_upper,
smoker_pval,
smoker_zval,
bmi_coef,
bmi_se,
bmi_hr,
bmi_ci_lower,
bmi_ci_upper,
bmi_pval,
bmi_zval,
nsubjects,
nevents,
partial_log_likelihood,
concordance,
log_likelihood_ratio_test,
log_likelihood_ndf,
log_likelihood_pval,
step_size,
])
def coxph_from_python(values,
isdead,
nbdays,
do_KM_plot=False,
png_path='./',
metadata_mat=None,
dichotomize_afterward=False,
fig_name='KM_plot.pdf',
penalizer=0.01,
l1_ratio=0.0,
isfactor=False):
"""
"""
values = np.asarray(values)
isdead = np.asarray(isdead)
nbdays = np.asarray(nbdays)
if isfactor:
values = np.asarray(values).astype("str")
if metadata_mat is not None:
frame = {"values": values, "isdead": isdead, "nbdays": nbdays}
for key in metadata_mat:
frame[key] = metadata_mat[key]
frame = pd.DataFrame(frame)
else:
frame = pd.DataFrame({
"values": values,
"isdead": isdead,
"nbdays": nbdays
})
penalizer = 0.0
cph = CoxPHFitter(penalizer=penalizer, l1_ratio=l1_ratio)
with warnings.catch_warnings():
warnings.simplefilter("ignore")
try:
with warnings.catch_warnings():
warnings.simplefilter("ignore")
cph.fit(frame, "nbdays", "isdead")
except Exception:
return np.nan
pvalue = cph.log_likelihood_ratio_test().p_value
cindex = cph.concordance_index_
if do_KM_plot:
fig, ax = plt.subplots(figsize=(10, 10))
kaplan = KaplanMeierFitter()
for label in set(values):
with warnings.catch_warnings():
warnings.simplefilter("ignore")
kaplan.fit(
#values[values==label],
nbdays[values == label],
event_observed=isdead[values == label],
label='cluster nb. {0}'.format(label))
kaplan.plot(ax=ax, ci_alpha=0.15)
ax.set_xlabel('time unit')
ax.set_title('pval.: {0: .1e} CI: {1: .2f}'.format(pvalue, cindex),
fontsize=16,
fontweight='bold')
figname = "{0}/{1}.pdf".format(
png_path,
fig_name.replace('.pdf', '').replace('.png', ''))
fig.savefig(figname)
print('Figure saved in: {0}'.format(figname))
return pvalue
def make_figure(df, pa):
df_ls = df.copy()
durations = df_ls[pa["xvals"]]
event_observed = df_ls[pa["yvals"]]
km = KaplanMeierFitter() ## instantiate the class to create an object
pl = None
fig = plt.figure(frameon=False,
figsize=(float(pa["fig_width"]), float(pa["fig_height"])))
## Fit the data into the model
if str(pa["groups_value"]) == "None":
km.fit(durations, event_observed, label='Kaplan Meier Estimate')
df_survival = km.survival_function_
df_conf = km.confidence_interval_
df_event = km.event_table
df = pd.merge(df_survival,
df_conf,
how='left',
left_index=True,
right_index=True)
df = pd.merge(df,
df_event,
how='left',
left_index=True,
right_index=True)
df['time'] = df.index.tolist()
df = df.reset_index(drop=True)
df = df[[
"time", "at_risk", "removed", "observed", "censored", "entrance",
"Kaplan Meier Estimate", "Kaplan Meier Estimate_lower_0.95",
"Kaplan Meier Estimate_upper_0.95"
]]
pa_ = {}
for arg in [
"Conf_Interval", "show_censors", "ci_legend", "ci_force_lines",
"left_axis", "right_axis", "upper_axis", "lower_axis",
"tick_left_axis", "tick_right_axis", "tick_upper_axis",
"tick_lower_axis"
]:
if pa[arg] in ["off", ".off"]:
pa_[arg] = False
else:
pa_[arg] = True
if str(pa["markerc_write"]) != "":
pa_["marker_fc"] = pa["markerc_write"]
else:
pa_["marker_fc"] = pa["markerc"]
if str(pa["edgecolor_write"]) != "":
pa_["marker_ec"] = pa["edgecolor_write"]
else:
pa_["marker_ec"] = pa["edgecolor"]
if str(pa["grid_color_text"]) != "":
pa_["grid_color_write"] = pa["grid_color_text"]
else:
pa_["grid_color_write"] = pa["grid_color_value"]
pl=km.plot(show_censors=pa_["show_censors"], \
censor_styles={"marker":marker_dict[pa["censor_marker_value"]], "markersize":float(pa["censor_marker_size_val"]), "markeredgecolor":pa_["marker_ec"], "markerfacecolor":pa_["marker_fc"], "alpha":float(pa["marker_alpha"])}, \
ci_alpha=float(pa["ci_alpha"]), \
ci_force_lines=pa_["ci_force_lines"], \
ci_show=pa_["Conf_Interval"], \
ci_legend=pa_["ci_legend"], \
linestyle=pa["linestyle_value"], \
linewidth=float(pa["linewidth_write"]), \
color=pa["line_color_value"])
pl.spines['right'].set_visible(pa_["right_axis"])
pl.spines['top'].set_visible(pa_["upper_axis"])
pl.spines['left'].set_visible(pa_["left_axis"])
pl.spines['bottom'].set_visible(pa_["lower_axis"])
pl.spines['right'].set_linewidth(pa["axis_line_width"])
pl.spines['left'].set_linewidth(pa["axis_line_width"])
pl.spines['top'].set_linewidth(pa["axis_line_width"])
pl.spines['bottom'].set_linewidth(pa["axis_line_width"])
pl.tick_params(axis="both",
direction=pa["ticks_direction_value"],
length=float(pa["ticks_length"]))
pl.tick_params(axis='x',
which='both',
bottom=pa_["tick_lower_axis"],
top=pa_["tick_upper_axis"],
labelbottom=pa_["lower_axis"],
labelrotation=float(pa["xticks_rotation"]),
labelsize=float(pa["xticks_fontsize"]))
pl.tick_params(axis='y',
which='both',
left=pa_["tick_left_axis"],
right=pa_["tick_right_axis"],
labelleft=pa_["left_axis"],
labelrotation=float(pa["yticks_rotation"]),
labelsize=float(pa["yticks_fontsize"]))
if str(pa["grid_value"]) != "None":
pl.grid(True,
which='both',
axis=pa["grid_value"],
color=pa_["grid_color_write"],
linewidth=float(pa["grid_linewidth"]))
if str(pa["x_lower_limit"]) != "" and str(pa["x_upper_limit"]) != "":
pl.set_xlim(float(pa["x_lower_limit"]), float(pa["x_upper_limit"]))
if str(pa["y_lower_limit"]) != "" and str(pa["y_upper_limit"]) != "":
pl.set_ylim(float(pa["y_lower_limit"]), float(pa["y_upper_limit"]))
pl.set_title(pa["title"], fontdict={'fontsize': float(pa['titles'])})
pl.set_xlabel(pa["xlabel"],
fontdict={'fontsize': float(pa['xlabels'])})
pl.set_ylabel(pa["ylabel"],
fontdict={'fontsize': float(pa['ylabels'])})
return df, pl
elif str(pa["groups_value"]) != "None":
df_long = pd.DataFrame(
columns=['day', 'status', str(pa["groups_value"])])
for row in range(0, len(df_ls)):
if int(df_ls.loc[row, pa["yvals"]]) >= 1:
dead = int(df_ls.loc[row, pa["yvals"]])
#print(dead)
for i in range(0, dead):
#print(i)
df_long = df_long.append(
{
'day':
int(df_ls.loc[row, pa["xvals"]]),
'status':
1,
str(pa["groups_value"]):
str(df_ls.loc[row, pa["groups_value"]])
},
ignore_index=True)
i = i + 1
elif int(df_ls.loc[row, pa["censors_val"]]) >= 1:
censored = int(df_ls.loc[row, pa["censors_val"]])
#print(censored)
for c in range(0, censored):
#print(c)
df_long = df_long.append(
{
'day':
int(df_ls.loc[row, pa["xvals"]]),
'status':
0,
str(pa["groups_value"]):
str(df_ls.loc[row, pa["groups_value"]])
},
ignore_index=True)
c = c + 1
df_dummy = pd.get_dummies(df_long,
drop_first=True,
columns=[pa["groups_value"]])
results = logrank_test(df_dummy.loc[df_dummy['status'] == 1,
'day'].tolist(),
df_dummy.loc[df_dummy['status'] == 0,
'day'].tolist(),
df_dummy.loc[df_dummy['status'] == 1,
'status'].tolist(),
df_dummy.loc[df_dummy['status'] == 0,
'status'].tolist(),
alpha=.99)
cph = CoxPHFitter()
cph.fit(df_dummy, duration_col='day', event_col='status')
cph_coeff = cph.summary
cph_coeff = cph_coeff.reset_index()
df_info = {}
df_info['model'] = 'lifelines.CoxPHFitter'
df_info['duration col'] = cph.duration_col
df_info['event col'] = cph.event_col
df_info['baseline estimation'] = 'breslow'
df_info['number of observations'] = cph._n_examples
df_info['number of events observed'] = len(
df_dummy.loc[df_dummy['status'] == 1, ])
df_info['partial log-likelihood'] = cph.log_likelihood_
df_info['Concordance'] = cph.concordance_index_
df_info['Partial AIC'] = cph.AIC_partial_
df_info['log-likelihood ratio test'] = cph.log_likelihood_ratio_test(
).test_statistic
df_info[
'P.value(log-likelihood ratio test)'] = cph.log_likelihood_ratio_test(
).p_value
df_info['log rank test'] = results.test_statistic
df_info['P.value(log rank test)'] = results.p_value
cph_stats = pd.DataFrame(df_info.items())
cph_stats = cph_stats.rename(columns={0: 'Statistic', 1: 'Value'})
#cph_stats
tmp = []
for cond in pa["list_of_groups"]:
df_tmp = df_ls.loc[df_ls[pa["groups_value"]] == cond]
km.fit(df_tmp[pa["xvals"]], df_tmp[pa["yvals"]], label=cond)
df_survival = km.survival_function_
df_conf = km.confidence_interval_
df_event = km.event_table
df = pd.merge(df_survival,
df_conf,
how='left',
left_index=True,
right_index=True)
df = pd.merge(df,
df_event,
how='left',
left_index=True,
right_index=True)
df['time'] = df.index.tolist()
df = df.reset_index(drop=True)
df = df.rename(
columns={
"at_risk": cond + "_at_risk",
"removed": cond + "_removed",
"observed": cond + "_observed",
"censored": cond + "_censored",
"entrance": cond + "_entrance",
cond: cond + "_KMestimate"
})
df = df[[
"time", cond + "_at_risk", cond + "_removed",
cond + "_observed", cond + "_censored", cond + "_entrance",
cond + "_KMestimate", cond + "_lower_0.95",
cond + "_upper_0.95"
]]
tmp.append(df)
df = reduce(lambda df1, df2: pd.merge(df1, df2, on='time'), tmp)
PA_ = [g for g in pa["groups_settings"] if g["name"] == cond][0]
if str(PA_["linecolor_write"]) != "":
linecolor = PA_["linecolor_write"]
else:
linecolor = PA_["line_color_value"]
if str(PA_["linestyle_write"]) != "":
linestyle = PA_["linestyle_write"]
else:
linestyle = PA_["linestyle_value"]
if str(PA_["markerc_write"]) != "":
markerColor = PA_["markerc_write"]
else:
markerColor = PA_["markerc"]
if str(PA_["edgecolor_write"]) != "":
edgeColor = PA_["edgecolor_write"]
else:
edgeColor = PA_["edgecolor"]
if PA_["show_censors"] in ["off", ".off"]:
showCensors = False
else:
showCensors = True
if PA_["Conf_Interval"] in ["off", ".off"]:
ConfidenceInterval = False
else:
ConfidenceInterval = True
if PA_["ci_legend"] in ["off", ".off"]:
CI_legend = False
else:
CI_legend = True
if PA_["ci_force_lines"] in ["off", ".off"]:
CI_lines = False
else:
CI_lines = True
linewidth = PA_["linewidth_write"]
edgeLineWidth = PA_["edge_linewidth"]
markerSize = PA_["censor_marker_size_val"]
markerAlpha = PA_["marker_alpha"]
CI_alpha = PA_["ci_alpha"]
markerVal = PA_["censor_marker_value"]
pa_ = {}
for arg in [
"left_axis", "right_axis", "upper_axis", "lower_axis",
"tick_left_axis", "tick_right_axis", "tick_upper_axis",
"tick_lower_axis"
]:
if pa[arg] in ["off", ".off"]:
pa_[arg] = False
else:
pa_[arg] = True
if str(pa["grid_color_text"]) != "":
pa_["grid_color_write"] = pa["grid_color_text"]
else:
pa_["grid_color_write"] = pa["grid_color_value"]
pl=km.plot(show_censors=showCensors, \
censor_styles={"marker":marker_dict[markerVal], "markersize":float(markerSize), "markeredgecolor":edgeColor, "markerfacecolor":markerColor, "alpha":float(markerAlpha), "mew":float(edgeLineWidth)}, \
ci_alpha=float(CI_alpha), \
ci_force_lines=CI_lines, \
ci_show=ConfidenceInterval, \
ci_legend=CI_legend, \
linestyle=linestyle, \
linewidth=float(linewidth), \
color=linecolor)
pl.spines['right'].set_visible(pa_["right_axis"])
pl.spines['top'].set_visible(pa_["upper_axis"])
pl.spines['left'].set_visible(pa_["left_axis"])
pl.spines['bottom'].set_visible(pa_["lower_axis"])
pl.spines['right'].set_linewidth(pa["axis_line_width"])
pl.spines['left'].set_linewidth(pa["axis_line_width"])
pl.spines['top'].set_linewidth(pa["axis_line_width"])
pl.spines['bottom'].set_linewidth(pa["axis_line_width"])
pl.tick_params(axis="both",
direction=pa["ticks_direction_value"],
length=float(pa["ticks_length"]))
pl.tick_params(axis='x',
which='both',
bottom=pa_["tick_lower_axis"],
top=pa_["tick_upper_axis"],
labelbottom=pa_["lower_axis"],
labelrotation=float(pa["xticks_rotation"]),
labelsize=float(pa["xticks_fontsize"]))
pl.tick_params(axis='y',
which='both',
left=pa_["tick_left_axis"],
right=pa_["tick_right_axis"],
labelleft=pa_["left_axis"],
labelrotation=float(pa["yticks_rotation"]),
labelsize=float(pa["yticks_fontsize"]))
if str(pa["grid_value"]) != "None":
pl.grid(True,
which='both',
axis=pa["grid_value"],
color=pa_["grid_color_write"],
linewidth=float(pa["grid_linewidth"]))
if str(pa["x_lower_limit"]) != "" and str(
pa["x_upper_limit"]) != "":
pl.set_xlim(float(pa["x_lower_limit"]),
float(pa["x_upper_limit"]))
if str(pa["y_lower_limit"]) != "" and str(
pa["y_upper_limit"]) != "":
pl.set_ylim(float(pa["y_lower_limit"]),
float(pa["y_upper_limit"]))
pl.set_title(pa["title"],
fontdict={'fontsize': float(pa['titles'])})
pl.set_xlabel(pa["xlabel"],
fontdict={'fontsize': float(pa['xlabels'])})
pl.set_ylabel(pa["ylabel"],
fontdict={'fontsize': float(pa['ylabels'])})
return df, pl, cph_coeff, cph_stats