Table 2 Overview of construction and rationale for inclusion of time dependent variables in the analysis of promotion

University hospital explanatory variables

University hospital yes/no (previous year)

One-year lagged variable that is 1 for working in a university hospital and 0 for all other hospitals.

To examine the influence of working in a university hospital in the previous year on the chance of promotion.

Time in university hospitals at rank

Begins with 0 and counts the cumulated number of years working in university hospitals at a particular rank.

To examine the impact of work experience in university hospitals on the chance of promotion.

Time in university hospitals at rank differentiated into 1–2 years, 3–4 years, 5–6 years, and > =7 years

Constructed from time in university hospitals at rank; four variables that switch from 0 to 1 in the first, third, fourth, and seventh years of working in a university hospital.

To gain a deeper understanding of the impact of short-term, mid-term, and long-term work experience in university hospitals on the chance of promotion.

Career stage-specific control variables

Time in rank

Starts with 1 and increases by 1 with each year in rank.

To examine the influence of occupational experience on the chance of promotion.

Time in rank squared

Squared variable of time in rank.

In connection with the variable time in rank, this variable models the growth of occupational experience and takes into account that the growth rate will decline over time.

Doctorate in medicine

Variable that switches from 0 to 1 the year a doctorate in medicine is obtained.

To examine the impact of obtaining a PhD in medicine on the chance of promotion.

Scientific degree

Variable that switches from 0 to 1 the year a habilitation is obtained.

To examine the impact of attaining a habilitation in medicine (highest scientific degree) on the chance of promotion.

Time to medical specialist

Starts with 1 and increases by 1 each year, remaining constant after the speciality is completed.

To examine the impact of the fast attainment of a medical specialization on the chance of promotion.

Medical specialty completed

Variable that switches from 0 to 1 the year a medical specialty is completed.

Completion of a medical speciality is compulsory for promotion from junior to senior physician. The variable indicates the effect of this occupational demand on the chance of promotion.

General control variables

Previous hospital tenure

Presents the total tenure at the previous hospital. The variable is constant for each year in the current hospital.

In connection with the movement variables, this variable controls for continuity with previous employers. It allows us to examine the impact of a longer tenure with the previous employer on the chance of promotion.

History of inter-organizational moves

Starts with 0 and increases by 1 for each change between hospitals.

To examine the influence of all employer changes over the course of a career on the chance of promotion.

Inter-organizational move

Variable that is 0 in years with no inter-organizational move and 1 in years with an inter-organizational move.

To examine the impact of an inter-organizational move on the chance of promotion.