The Gemara (Bava Metzia 77a) writes that employees (poalim) and independent contractors (kablanim) are governed by different laws. For instance, poalim may quit in the middle of a job even if they committed themselves via a kinyan, while kablanim who committed via kinyan may not quit. Moreover, poalim who quit are entitled to a prorated salary, i.e. half their wages for half the job, while kablanim sometimes receive less than half their wages for half the job. Furthermore, if a poel was grossly overpaid or underpaid, his contract is still binding, while a kablan who was overpaid or underpaid is entitled to restitution (Rambam Hilchot Mechirah 13:15).

There are three ways to determine whether a worker is a poel or a kablan. First, a worker paid per hour is a poel, while one paid per service is a kablan (Maggid Mishneh Hilchot Sechirut 9:4). According to this, a poel is bound to his boss, while a kablan is bound to his labor. A kablan is distinguished by his responsibility; if he is efficient and creative, he will keep more time for himself, while if he is slothful and incompetent, he will suffer the consequences. In contrast, a poel who works efficiently simply will be assigned another task by his boss.

It sometimes is difficult to determine how a worker is paid. For instance, doctors are compensated for the services they provide and also for the time they spend. Two procedures that take equal time can have different costs, but one procedure can cost one amount if it takes a certain measure of time and cost more if it takes longer. Doctors in private practice perceive of themselves as charging for service. Hence, based on this criterion, it is most likely that such doctors are kablanim.

A second criterion for distinguishing between a poel and a kablan is that a worker who must complete his job within a set time is a poel, while one who can complete it at his leisure is a kablan (Terumat HaDeshen 323). This definition downplays responsibility and instead emphasizes freedom. It ensures that workers’ freedom is preserved, since kablanim can, by virtue of their commitment’s nature, freely choose how to use their time, while poalim have similar freedom by Torah fiat.

According to this, it is unclear whether private doctors or poalim or kablanim. When patients make an appointment, does this obligate the doctor to meet them, if not at the exact appointment time, at least reasonably soon afterwards? Or is the appointment simply a suggestion about when the doctor is most likely to choose to meet them? According to the media, a doctor in Las Vegas was fined $250 for keeping his patient waiting, but a doctor in Dallas was exonerated for a similar offense. Hence, there still is confusion in the public mind about whether or not doctors may complete their job at leisure.

The third criterion for distinguishing a poel from a kablan is that a worker who improves an object may be a kablan, but one who makes no concrete improvement can only be a poel. Rabbi Soloveitchik explained that a kablan is entitled to restitution because he acquires the object upon which he labors, and the object’s owner must pay him to relinquish that acquisition. For this reason, the laws governing paying a kablan correspond to the laws of purchasing an item, not to the laws of hiring workers. For instance, an employer need not pay a kablan with currency, just as he need not pay a merchant with currency. Moreover, he need not pay his kablan within the day of completing his work; he may wait until he receives the item, just as he need not pay a merchant until he receives his merchandise. (Rambam Hilchot Sechirut 11:3) In contrast, poalim must be paid with currency and must be paid within the day.

According to this, since doctors cannot acquire a share in their patients, doctors cannot be kablanim, and rather must be deemed poalim.