{'fraction_non_alphanumeric': 0.015517241379310345, 'fraction_numerical': 0.010919540229885057, 'mean_word_length': 4.962328767123288, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Adaptability of a broad spectrum of randomly selected patients to a variable design progressive lens: report of a nationwide clinical trial.

BACKGROUND
Through continuously improved design, progressive lenses have become the presbyopic lens style of choice by some practitioners. Studies have shown them to be preferred by patients but growth has been modest over the last 35 years. Many practitioners may remember early problems now eliminated. This stigma may prevent many patients from benefiting from improved technology.


METHODS
An invitation to be involved in a study was sent to practitioners nationally. Each was asked to induct ten patients; obtaining personal and prescription information as well as preferences, adaptive experience, age and occupation. Practitioners were asked to target current presbyopes so that conversion success could be better evaluated.


RESULTS
The 1,713 patients in the study had an average age of 49.4 years, 28 percent of whom were currently wearing bifocals or trifocals. Of these, 85 percent preferred the study PAL over their current multifocal. Most adapted in less than two weeks. A similar percentage was also seen across the variety of occupations in the study.


CONCLUSIONS
With a confidence level of 95 percent, the findings of this large scale study regarding acceptance of the study PAL were extremely positive. Success is apparently influenced by fitting skills as most failures were recorded in a few isolated practices where acceptance level dropped to less than 40 percent. Without these, the balance of practitioners averaged over a 90 percent acceptance level in patients converting from a wide range of lens styles, as well as patients of a wide variety of ages and occupations.