Depression by Age
Arthur kanyoza
2025-12-18
Depression in Europe
Define Depression Scale CES-D8
With ESS data depression is measured by the CES-D8 scale. First we load the data, check reliability, and compute the score:
Depression values across Europe can than be then summarized as follows:
summary(df$cesd8)## Min. 1st Qu. Median Mean 3rd Qu. Max. NA's
## 1.000 1.375 1.625 1.695 2.000 4.000 799In general, the CES-D8 scores show a unimodal, slightly right skewed distribution:
summary(df$cesd8)## Min. 1st Qu. Median Mean 3rd Qu. Max. NA's
## 1.000 1.375 1.625 1.695 2.000 4.000 799Hypothesis
Depression varies with age because biological, psychological, and social conditions change over the life course: it often rises in adolescence due to developmental and social stress, stabilizes or declines in midlife as coping improves, and may increase again in older age due to illness, loss, and loneliness.
In general, we expect an increase of depression scores with increasing age.
To test our hypothesis, we estimate a linear regression model.
model = lm(cesd8 ~ agea, data=df)
summary(model)##
## Call:
## lm(formula = cesd8 ~ agea, data = df)
##
## Residuals:
## Min 1Q Median 3Q Max
## -1.03759 -0.36137 -0.07893 0.26964 2.39464
##
## Coefficients:
## Estimate Std. Error t value Pr(>|t|)
## (Intercept) 1.53726 0.04843 31.744 < 2e-16 ***
## agea16 0.07411 0.05472 1.354 0.175597
## agea17 0.03023 0.05493 0.550 0.582030
## agea18 0.10798 0.05461 1.977 0.048013 *
## agea19 0.12499 0.05370 2.328 0.019935 *
## agea20 0.11668 0.05428 2.150 0.031578 *
## agea21 0.09496 0.05439 1.746 0.080804 .
## agea22 0.09448 0.05425 1.742 0.081582 .
## agea23 0.10096 0.05440 1.856 0.063471 .
## agea24 0.10552 0.05365 1.967 0.049232 *
## agea25 0.15896 0.05388 2.950 0.003177 **
## agea26 0.11634 0.05404 2.153 0.031342 *
## agea27 0.09818 0.05426 1.809 0.070394 .
## agea28 0.13110 0.05380 2.437 0.014825 *
## agea29 0.13511 0.05347 2.527 0.011508 *
## agea30 0.12470 0.05335 2.338 0.019416 *
## agea31 0.09238 0.05364 1.722 0.085059 .
## agea32 0.09954 0.05306 1.876 0.060645 .
## agea33 0.12745 0.05249 2.428 0.015183 *
## agea34 0.10673 0.05269 2.026 0.042797 *
## agea35 0.12177 0.05272 2.310 0.020900 *
## agea36 0.05820 0.05297 1.099 0.271892
## agea37 0.11597 0.05299 2.188 0.028642 *
## agea38 0.07890 0.05232 1.508 0.131556
## agea39 0.06810 0.05239 1.300 0.193618
## agea40 0.11542 0.05273 2.189 0.028618 *
## agea41 0.12506 0.05237 2.388 0.016955 *
## agea42 0.09132 0.05228 1.747 0.080680 .
## agea43 0.10377 0.05231 1.984 0.047285 *
## agea44 0.14334 0.05220 2.746 0.006032 **
## agea45 0.14633 0.05240 2.792 0.005235 **
## agea46 0.12806 0.05253 2.438 0.014774 *
## agea47 0.10534 0.05234 2.012 0.044179 *
## agea48 0.09292 0.05229 1.777 0.075555 .
## agea49 0.11420 0.05197 2.197 0.028005 *
## agea50 0.11947 0.05216 2.291 0.021992 *
## agea51 0.15321 0.05214 2.938 0.003301 **
## agea52 0.15323 0.05194 2.950 0.003181 **
## agea53 0.15182 0.05185 2.928 0.003413 **
## agea54 0.14496 0.05202 2.786 0.005331 **
## agea55 0.18683 0.05210 3.586 0.000336 ***
## agea56 0.16667 0.05199 3.206 0.001349 **
## agea57 0.18987 0.05188 3.660 0.000252 ***
## agea58 0.17107 0.05163 3.314 0.000921 ***
## agea59 0.20262 0.05194 3.901 9.59e-05 ***
## agea60 0.17041 0.05196 3.280 0.001040 **
## agea61 0.13789 0.05201 2.651 0.008022 **
## agea62 0.16134 0.05230 3.085 0.002038 **
## agea63 0.14219 0.05194 2.737 0.006195 **
## agea64 0.15870 0.05160 3.076 0.002102 **
## agea65 0.13682 0.05200 2.631 0.008510 **
## agea66 0.16096 0.05196 3.098 0.001950 **
## agea67 0.15599 0.05187 3.007 0.002636 **
## agea68 0.16188 0.05178 3.126 0.001773 **
## agea69 0.15090 0.05208 2.898 0.003762 **
## agea70 0.17359 0.05228 3.321 0.000899 ***
## agea71 0.14735 0.05257 2.803 0.005067 **
## agea72 0.15880 0.05256 3.021 0.002519 **
## agea73 0.20567 0.05269 3.904 9.49e-05 ***
## agea74 0.22546 0.05259 4.287 1.81e-05 ***
## agea75 0.23595 0.05273 4.475 7.68e-06 ***
## agea76 0.24728 0.05320 4.648 3.36e-06 ***
## agea77 0.26888 0.05350 5.026 5.02e-07 ***
## agea78 0.33565 0.05412 6.202 5.62e-10 ***
## agea79 0.21659 0.05503 3.936 8.30e-05 ***
## agea80 0.25237 0.05483 4.603 4.18e-06 ***
## agea81 0.29689 0.05606 5.296 1.19e-07 ***
## agea82 0.37678 0.05617 6.707 2.01e-11 ***
## agea83 0.29440 0.05688 5.176 2.28e-07 ***
## agea84 0.43039 0.05746 7.490 7.02e-14 ***
## agea85 0.45192 0.05931 7.620 2.60e-14 ***
## agea86 0.42201 0.06095 6.923 4.47e-12 ***
## agea87 0.50033 0.06364 7.861 3.90e-15 ***
## agea88 0.27524 0.06725 4.093 4.27e-05 ***
## agea89 0.30149 0.06917 4.359 1.31e-05 ***
## agea90 0.46923 0.05832 8.046 8.78e-16 ***
## ---
## Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
##
## Residual standard error: 0.4939 on 39052 degrees of freedom
## (1028 observations deleted due to missingness)
## Multiple R-squared: 0.02197, Adjusted R-squared: 0.02009
## F-statistic: 11.7 on 75 and 39052 DF, p-value: < 2.2e-16# Oops, why so many parameters?plot(df$agea,df$cesd8)
# what the heck is happening here???